Grand Theft Auto 3 is 15th Today! Happy Birthday!
Check out Razors guide on how to get GTA3 running in all its glory on a modern computer:-
The PC release of GTA3 is now very outdated and even on release it was missing many features that both the Xbox and PS2 ports had such as reflections, this small tutorial and the pack it comes with aims to resolve these issues and bring new life to your Grand Theft Auto III installation.
Please note that this has been tested only on the Steam release of GTA3 but it should work with retail releases provided they are up-to-date.