You mean you want something like an emulator? Some says its illegal. I once had it but I've lost the software on a cd.
I really enjoy playing my PS2 over the years. Now PS3 like what they say, will come around approximately late 2005/early 2006. I think that's too bit early as PS2 is still rookie (!). I will sell my PS2 next year.
I felt like its too soon but I will enjoy the PS3 release though.