Marker is a command palette for the terminal. It lets you bookmark commands (or commands templates) and easily retreive them with the help of a real-time fuzzy matcher.
"XBookmarks" for "XMPP Bookmarks". It is the Firefox implementation of XEP-0048: http://xmpp.org/extensions/xep-0048.html. You simply need a Jabber account and you can use it. Currently it is very basic, though functionnal, as the XEP is.