Why won't my xmodmap command run on startup/login?

Put it in ~/.Xmodmap. Some distro look for ~/.Xmodmap instead of ~/.xmodmaprc. It works for me on Fedora 16.

Depending on your distribution the ~/.xsession file is executed (a shell script) when logging into X. And/or the ~/.Xmodmap file is sourced by an xmodmap process.

The ~/.profile file is only executed by a login shell (with or without X), thus it is not the right place