This page contains a feed of commands (source) for Ubiquity.

Miscellaneous commands

strikethrough
Strikes through the selected text, like this, for use in Gmail compose, to-do lists, etc.
monospace
Changes selected text to a monospace font, like this, for use in Gmail compose, etc.
zap-stylesheets
Remove CSS styles from the current page. Converted from a bookmarklet from squarefree.com
note-in-google-reader
Converted from a bookmarklet from Google Reader
google-site-search

Search within the site you are viewing. Modified version of this command. Added a list of subdomains and subdirectories you can search within by clicking. This is kind of hard to explain, so here is a picture:

Ubiquity site search showing multiple domains

Another option would be to display the actual search results in the preview, like a regular Google search, and let the site be narrowed down as part of the command, but I'm not sure how you would specify a certain bit if the path without typing it all out.

Web archive commands

coral-cache
Goes to CoralCDN's cached version of the current page.
google-cache
Goes to Google's cached version of the current page.
google-cache-text-only
Goes to Google's text-only cached version of the current page.
wayback-machine-list
Lists all archived versions of the current page on the Internet Archive's Wayback Machine. Converted from a bookmarklet I made.
wayback-machine-latest
Goes directly to the most recent archived version of the current page. Converted from a bookmarklet I made.
webcite-cache
Goes to WebCite's archived version of the current page.

All these archive commands should be integrated into a single "Resurrect page" command that includes everything from the Add-On:

and displays all the available options in the preview. I'll try to do this eventually...