I've got 10, but 5 are on the computer in the city I live in for my job and 5 are on the computer where I spend weekends and holidays. I've got 3 day games and 2 night games on each one, so it's not too difficult to keep track.

Moonlyght, I had just started Plant Tycoon for the 3rd or 4th time and I had to quit...I kept forgetting my plants!