Directory "Bookmarking" in Linux

cdargs is the best tool for bookmarking a directory : http://www.youtube.com/watch?v=uWB2FIQlzZg

There is also bashmarks project (for bash shell), which uses one-letter commands for managing directory bookmarks:

s <bookmark_name> - Saves the current directory as "bookmark_name"
g <bookmark_name> - Goes (cd) to the directory associated with "bookmark_name"
p <bookmark_name> - Prints the directory associated with "bookmark_name"
d <bookmark_name> - Deletes the bookmark
l                 - Lists all available bookmarks