Let's see, there are quite a few games that I regret buying:
1: Alien shooter (and improvement), Alien shooter 2 (and improvement), zombie shooter:
I mean, what the hell are those games? I bought them all in one pack.
Many hours of game play with 10 missions and a survival mode Yea right, I played through 5 missions in one hour before getting bored. Tried survival mode, it basically takes all the good things from the campaign, but still not enough to keep my interest for longer then 30 minutes
About 1,000 monsters on each map, showing up to 100 monsters simultaneously on one playing screen Yup, they're right. 100 monsters simultaneiously on screen, too bad they kept running against walls trying to reach me. They had the simplest AI ever, even for zombies 
Arcade action combined with sophisticated RPG elements Arcade action: Yup. Sophisticated RPG elements? You find experience blocks in crates and sometimes, monsters drop them. If you level up, you get 1 point you can spend on either speed, strength, health or accuracy. Sophisticated? Nah, you could only upgrade a certain skill 4 or 5 times)
A variety of playable characters, each featuring unique abilities [b]Male and female, female is faster and more accurate. Male is stronger and healthier >.>
More than 50 types of weapons - now you can not just kill but also burn, freeze and even diminish the enemies About 10 weapons, each is upgradeable, most likely 5 times. Lol
Highly imaginative selection of zombies/aliens Alright, check some pictures. Everything looks like it's been ripped straight away from Resident Evil, Aliens and some other movies. Wtf
2: X3: Terran Conflict.
When I first loaded the game, there was no sound or anything. No one could help me with this problem. My computer was more then enough to play it, but somehow, customer support had no solution to the sound problem >.> I don't know, somehow, I felt incredibly sorry for buying this game, as I was really low on money (yeayea, it was irresponsible to buy games while low on money
)
3: Virtual Families.
O...my...god...This game was aweful. It was basically a sims game, only the actions took a ridicilous amount of time to complete and it looked terrible. Seriously, I've played Virtual Villagers or whatever it was called, I didn't really like it, but it wasn't that bad either, but this...this...this...thing was. I don't mind cleaning up the garbage but does it have to take 5 minutes for the player as well? lol
Well, there are a lot more games that I regretted buying, but these 3 just really stood out.