tomsrtbt - www.toms.net/rb - the distro that made me go this way...
uClibc - www.uclibc.org - the C library
links - atrey.karlin.mff.cuni.cz/~clock/twibright/links/index.html - the web browser wich is the main focus of this distro. I'm using its SVGAlib UI but it looks good on Xwindow too. Play with it!
busybox - www.busybox.net - "the swiss army knife of embedded Linux"
freshmeat - freshmeat.net - you probably know this one ;-)