As I've always been interested in (maybe even obsessed with) computers/-games, I admit that other platforms lured me away from the Amiga. I always return though.
At first it was the Super Nintendo which made me forget my Amiga. After that it was the PC with its colourful point-and-click adventures and RPGs like Might and Magic. Later on I was obsessed with my Nintendo64 just to return to the PC for some more (online-)RPGs.
Ironically though, it was the culmination of all my wishes that made me long for simpler games and my faithful Amiga once again: Oblivion. As a Morrowind addict I hungered for more, but Oblivion just felt empty and I haven't touched a PC game for almost a year now.
I guess that the temptations of the Wii and a retry of Oblivion or maybe Gothic 3 will make me set aside my Amiga once again, but not just yet...
BTW: Funny that you mention the PSone. Never liked that one, nor the PS2 for that matter. And I'm not really a Nintendo fanboy either.