Right now, I'm playing Grand Theft Auto III. After seeing the GTA pack on Steam for £11.89 last weekend, I had to get it right away and give the GTA franchise a good go and I must say, I'm impressed at GTA3 so far. One of the things I really like about this game is having custom soundtrack. :D
I did give GTA1 a go on Saturday, but I'm afraid it didn't keep my interest long enough. I came across several issues in the game. Fortunately, this was only the beginning of the series.
The other two games I'm playing are Bioshock and Psychonauts (for the third time, lol). I may need to cut down some time on GTA3 so I can focus on these two games since I've got more than enough time to play it for a few hours each day.