OVAs (Original Video Anime) are small spin off episodes of established series. mostly they highlight bit characters or extra story line to the parent series. Other times they offer "What if" scenarios (like Ed's Grand kids OVA). They can be stand alone episodes, hour long specials, 3-6 part series or even movies (if i recall right...).
Here you can suggest ideas you would like to see. Feel free to make up silly ones for your own amusement.

Personally there are two I really want;
1) Social Welfare agency meet Lagoon Company. (Series: Black Lagoon and Gunslinger girl. 30 min-hour long show)
Balalaika has business in Rome and hires the Lagoon company to be a scout group (go to Rome first and make sure things are safe) while Hotel Moscow is still getting ready. Italy's SWA get wind of this and decide to eliminate the Lagoon Company in hopes it stops Balalaika and her boys from coming along.
Plot doesn't really work but this is really about the action. The idea of the Gunslinger girls facing off against Revy and Dutch is great. Better through in Eda and Shenhua as well for balance.

2) Matsuda and the Cheif (Series: Death Note. 3-5 half hour episodes, maybe an hour long finale including a fight in a clock tower)
The simple premiss is a parody of the old 70/80's cop shows (set in an alternate universe where certain people didn't die) with the older "by the book" cop and the younger "willing to use underhand/immoral tactics" cop.
Every episode they deal with two cases. One is wrapped up in the episode and the other, a killing spree, carries through the series and is dealt with in the finale. (Death notes and Shinigami may be involved and Near/Aizawa or Melo may make an appearance.) Through Yagamis use of old school methodology and Matsudas "street smart" (a point of endless clichéd comedy) they will solve each crime with gutso. At the end of each episode someone will make a lame joke and everyone will laugh.
And in a special role written just for him Mogi will play a friendly pimp, much like Huggy bear.

Now lets hear your ideas.

Well, I've been searching the internet and I guess these two were the ones that appealed to me the most: Ai No Kusabi and Earthian. *yaoi and shounen-ai, what else?*

Oo, wait, is Gravitation an OVA? *yes, MORE shounen-ai!*
Maybe mix sounen-ai wit more shounen-ai, mix those with Mirage of Blaze: Rebels of the River's Edge, ooo

I think you have a bit of a typo there^ . Anyway, I would have to say mine would be for 'Negima!' ('Maou Sensei Negima!')

Negi decides to go back to Wales to visit his older sister(I can't remember her name right now) and Anya. He invites Asuna, Konoka, Setsuna, Yue and Nodoka to come along. But Ayaka, being torn up about her beloved sensei leaving her view for more than a night, and that he'll be 'all alone' with Asuna(her worst enemy and best friend(<-sorta), she decides to tag along. The rest of class 2-A decides to go with Ayaka. Minus Evangeline because of her curse, Chachamaru because she refuses to leave her Evangeline's side, and Sayo because she's still bound to the clock tower. When Negi and his invites realize that Ayaka and the other 22 girls are with them, he has to try to hide the fact that he's a wizard from the people he didn't bring along. To bad Anya and his sister don't realize that.

It's not that good but if you've seen Negima! then you'd understand it better .

^Typo there as well

Sorry, sorry, not from England here. Then how is 'Whales' spelled? As in the place, of course ?

@Little Washu - *cough Wales cough* I think. ^^

OVA I want to see is... Samurai Champloo. Something funny will be nice. ^^

I wouldn't mind seeing a Chevalier D'eon OAV in which the characters actually get some relationship development. The series really could have benefitted from some fillers for the sake of building bonds or personality for the characters. I had wanted to see what Lia and D'eon's relationship was like when they were alive; more background on their home life and guardianship, their friendship with Anna (and something that might make me care about Anna more), etcetera. One of the things that they totally could have played on, but never did, was the prospect of Durand angsting over (and possibly Lusting after), D'eon in drag and how much he looks like his sister. It could have been highly uncomfortable and angsty, or it could have been funny as crap with the right amount of alcohol thrown in.

Otherwise, I'd just like to see the OAV jam packed with (even) higher-budget animation that's stuffed full of gratuitous PRETTY! I may be shallow, but gosh, are Chevalier's swordfights fun to watch. I wish we could see the same effort afforded towards some other nice scenes, such as ballroom dancing or some of the more tense symbolic images.

Seriously, I'm such a sucker for a well animated dance scene. If we only got a 5 minute OAV entirely of well choreographed (And in-character) dancing with the CD'E characters, I'd be a HAPPY PANDA. (This is just my silly personal fantasy, though.)

Mm, Death Note would be a treat! Or Fruits Basket.

Yeah, they could stick whatever important stuff in the manga that they left out in the anime into the Fruits Basket OVA. XD When it ended, I wanted more. >_>;;;

Or maybe Gakuen Alice...another anime that ended too fast. Perhaps the GA OVA chronicles Mikan's next year in the academy, maybe after a long-awaited return to her grandfather...

A lot of animes leave me hanging when they end. XDDDDD Of course, that's why manga exists...

A Tales of the Abyss OVA would be divine.

They just released the Tales of Symphonia OVA this week, and Abyss has proven to be quite popular...maybe not on the same vein as ToS [not nearly as hyped, seeing how Symphonia was a GCN exlusive and one of the very few RPGs to be on the system], but the characters and story are definately enough to make it OVA-worthy.

Another would be some sort of OVA focusing on the events of Xenosaga episodes two and three. They already made a series based on episode one, so I'd like to see what they could do with episodes two and three.

And finally, a Pokemon OVA. Or two. One could focus on the creation of the Pokemon world [as Diamond and Pearl focus alot on time, space, dimensions, and all that fun stuff], or...an OVA with human Pokemon. That would pwn.

And there's my crappy ideas. xD

A Fruits Basket OVA would be nice. They could introduce the other Zodiac members from the manga that we didn't see in the anime. What were they again? The Rooster and the Horse? Yeah, those two. Or something with Shigure, he never really got as much attention as the others did.

Full Metal Alchemist OVA,how Alphonse got married or how the Elric brothers look like at 20 or something.Maybe an OVA about Roy and Riza,or Gracier and Elysia,or maybe how Winry is.
Fruits Basket would be okay also.I wanna see how Tohru and Kyo are.Including Yuki.