Docs (including examples) are at http://www.ctan.org/tex-archive/macros/latex/contrib/algorithmicx/ if you're curious. Bo's suggestions resonate with me for code listings, but for mathematical statements of algorithms, I prefer algorithmicx.
I have not used listings to write pseudocode, but I guess the 'escape to latex' mode is enough to have mathematics inside a code-like structure, with syntax highlighting. At least listings supports "a $\le$ b" easily. algorithmicx may better suit your need though. Bo
