Both. I have 2 Amigas (A1200+8MB+4GB HD and CD32+SX1... I suppose it counts as a computer), and 2 PCs (an Athlon XP 1800+ and a Celeron 500 laptop I got for free).
I use the Amigas mostly for gaming, nothing beats the feeling of playing Turrican 2 on a real Amiga connected to a 21" TV through a SCART-RGB cable. It's just "not the same".