I figured i tend to use a lot of the same personal scripts across multiple computers, so i moved my bin into a synced Dropbox folder, and symlinked it from my home directory.
A script similar to below should get that set-up:
ln -s ~/Dropbox/bin ~/bin
echo "export PATH=~/bin:$PATH" >> ~/.profile
.profile should work for OS X. For linux, it might make sense to replace .profile with .bash_profile or .bashrc.