the "racing" factor (like in the Colin
I second that, World Racing is great for driving around aimlessly,
discovering things, throwing expensive cars off of mountains etc. Though the
main game is fun as well. Physics and force-feedback are quite enjoyable.
Where is World Racing 2 BTW? It's long overdue, can't find it anywhere in
shops in the Netherlands.
Vice City is great for driving around and exploring, the 80's atmosphere is
awesome. It's great to just hijack any car or bike you fancy and then drive
it around at high speeds until it's completely wrecked. No force-feedback
though and the physics aren't that great.
Driv3r can be fun as well if you just want to drive around exploring the
city.
For more mindless fun, at insane speeds, mass destruction and great
force-feedback, see if you can find Rollcage 1 or 2. What a feeling, when
you're driving on the ceiling.