Me too.  The AI in MS. Pac-Man was a fucking monster!  It was nothing like the 80's original.  Those ghosts were out for blood!

 I used to score 200,000 + points on the original, but my best on the xbla version is in the 50,000 to 60,000 range.

On probably 90% of the games, yes.  There are a few earlier releases that let you use cheat codes.

ive done it here and there if its easy to do

like leave dead rising on all day while at work, get the 24 hours outdoors achievement

but im not gonna sit there in mass effect casting spells on the mako for 4 hours

I know in BIA Hells Highway You can Cheat on the Time Played one.

I havnt done it myself yet .

I imagine it is the same for PS3.

You go to time settings on your console and mess about with that.

Anyway heres a link to the walkthrough if you want to check it out.

Also you can get all kilroys and recon points.

http://www.mahalo.com/Brothers_In_Arms_Hells_Highway_Walkthrough

Some people use game save cheats, hosts of matches can lag online games allowing them to win all the time, have someone else use your account, hacks to unlock the achievements for XBox 360 games. But if you get caught you have your XBox 360 console banned from XBox Live and have your Gamer score reset back to 0 points. I personally do not cheat and I have earned all of myGamer Score by myself

So if I used them in BIA I could get banned?

Potentially banned but first you would receive a warning or two. People who cheat online spoil the fun for others and man they should not be able to cheat online. PC gaming is rife with cheats who have mods in the games that make them invincible. Just not fun for people who do not cheat when playing against cheats.

In Xbox version of Bioshock you can get ''I choose the impossible'' (complete the game on survivor difficulty without using vita chamber) achivment by just changing the difficulty in the final battle with Atlas. You cant do that on PS3 verion. I dont know why