Have an old PC, which linux distro?

I have an old gaming pc running MS windoze 98 gold (not too different than the first edition, idk the difference, but it says gold edition at boot) that is pretty much broken (don't like it anyway). It has a Pentium III processor, at 550 MHz, and (i think) 256mb of ram. I would like a modern linux distro.

I know about Fedora, but I don't have enough ram.

Not Ubuntu.

I've used Puppy Linux before, and I am thinking about TEENpup Legacy 2009, but hoping for better options.

DSL doesn't work (Something with the XWindow config that I cant change).

Blueflops is too basic.

Anybody got any other ideas? Links to lists are appreciated, too.