I'm still going for 100%. I think all thats left are the stunt jumps. Then I'm going to try for the Liberty City Minute achievement (beating the game in under 30 hours).
I don't get to play as much as other people. I have a full time job during the day, a house to take care of, a girlfriend that I live with, and people to see and things to do on weekends.
But I still manage to have fun running around creating chaos. People say you can't spend money? Seems to be taking care of my hospital bills just fine! I keep getting killed and don't care.
Some fun things I did recently were reaping havoc on Happiness Island with an Annihilator. Then getting out and using weapons to continue the mayhem. If you find the row of forklifts, shoot one at either end in the gas tank and watch the domino effect.
Also, get a white car and drive down the sidewalks plowing into people. Custom paint job.