I regret buying Defend Your Castle; it's just so repetitive.

Pokemon Rumble faces the same problem but I can live with that purchase. I honestly had a lot of fun beating it, but it is a bit expensive for a WiiWare game.

Besides Overturn I'd have to add:

Driift Mania: I've don't like how it controls. Feels like I have to fight the controls with my car going in the wrong direction. Ruined my enjoyment of the game. A demo would have saved me from this purchase.

Adventure Island: The Beginning: While I loved alien crush and star soldier was good though short this one could have used a lot of polish. Times when your spear just hits an invisible wall are annoying as well as a lot of cheap deaths. There is still fun to be had it just could have been better and gets annoyingly frustrating at times.

I also didn't enjoy bomberman blast as much as I thought I would though I can't fault the game too much.

I like that game on the PC, I use a ps2-style USB controller to play it with

I Regret Nothing!
_{Pokemon Ranch}

If Retro City Rampage would come out I doubt I would regret it....does anyone know where that game is??? I thought there was once a release date for today?

Mario and sonic at the London 2012 Olympic games - 3DS version
I thought the game play was just generally boring compared to the superior prequels. They just felt too Mario party-ish. Not that i don't like Mario party, its just that this game shouldn't be like that. The first game was nice because of the complexity of the events, and it used the touch screen a lot more.
Sure, the game looks nice and all, but that doesn't matter if the game play is dull. The only music i enjoyed in this game was the music in the walk-race event, which isn't even original music. Maybe i'll trade it in, see if i can get puzzle bobble universe, because i know for sure ill never get bored of it.

3DS Games(Inluding 3DSWare and VC)

Super Monkey Ball 3D
Super Street Fighter IV: 3D Edition
Zen Pinball
Balloon Kid
Cat Trap
Mr Game & Watch Collection
Avenging Spirit

Ya really, seems like this game has been in development for years. It's basically being developed by one guy only who basically poured his entire life savings into it. I really hope it doesn't bomb!

I think Sonic Chronicles for the DS it was crap and I can't believe I bought it at full price.

Mw3: Defiance is the worst game i ever bought!

@MrArcade:
@WaveBoy:
@mamp:
@runeacer74:
Isn't this the WiiWare section?

I regret nothing, because if I hadn't downloaded the games I downloaded, I wouldn't know if they are good or bad.

Last mediocre game I got was Frogger Returns.
Newton Vs The Horde has a pretty interesting concept, but has some unpolished gameplay mechanics.
The rest of my recent downloads all get 7/10 or better,
even though I'm somewhat annoyed and disappointed by the frequent crashes in Zombie Panic in Wonderland in the 2P co-op mode.

So far, I don't have any regrets. Although I do have a few games I downloaded from Wiiware that, when I want to sit and play a game for a minute, I always tend to pass up.

It is no wiiware but i regret buying Eternal Champions (genesis).

I am going to get a lot of backlash from this, but World of Goo. I simply do not like it, and just found it really boring. Plus I could of got it for much cheaper on PC (I paid £15 for it because I didn't have a debit card back then to buy points straight from the Wii Shop Channel, curse you Blockbuster for your overpriced goods!)

Dr. Mario - way too difficult for me. And Sonic.

I could've done without LostWinds or Dr. Mario Online Rx. Neither of them are "bad", but I don't play the latter anywhere near enough to have warranted spending money on it (I play the freaking Dr. Wario mini-game in WarioWare more often), and while it's presentation was nice, I found the gameplay in LostWinds to be rather dull.

For non-WiiWare titles... I still regret spending $10 on Quest 64.

Sonic Unleashed...

2 fast 4 gnomz
DR mario
Defend Your Castle
zombie panic in wonderland
super mario kart

Contra Rebirth; for 200 Wii Points less, I could of bought Contra III which Rebirth is a rehash of.

I don't regret onslaught but I regret not playing it more, being the only FPS game I own

Your mom. Terrible graphics, long load times, and no replay value makes this a regrettable purchase.