BTW if you're looking for memory card files for use with pSX Emulator, TheCylo, pSX will recognise most or all raw formats: not only .bin, but .mcr, mcd, etc.
Also, check out
Aldo's Tools (a great Playstation emulation resource) for memory editors and converters.
Edit: that's not to say Shendo's MemcardRex isn't good - I haven't tried it yet, but I would suspect it's excellent.