Install these in Chrome, Safari, or Firefox with Greasemonkey.
Twitter avatar in menu
See which account you're logged in under at a quick glance
Magnet Link Display
magnet:// links and other P2P URLs prominently. Great for sites that hide the real links between obnoxious "download" ad banners or open pop ups when you click on them.
Enhance App.net by adding useful features to the Alpha web app.
- Repost — Easily repost/share another user's post
- Image previews — See images from posts without having to open them
- Twitter character count — Ensure your post will fit within Twitter's 140-character limit when you crosspost to both networks using twapp, ifttt or other services.
Compact styles for Google Reader
Cleans up Google+ Post pages. Currently only eliminates the gigantic avatar in the sidebar.
Redirect from WikiTravel to WikiVoyage
When landing on a WikiTravel.org article, this script automatically redirects to the corresponding article on WikiVoyage.org.
This brief description of WikiVoyage's creation reflects my reasons for preferring it. Despite updating my own bookmarks and shortcuts, this script is still necessary because links to WikiTravel often show up in search results, blogs, etc.
Legible (large-font) styles for Flickr
Probably not useful for anyone else, this script will determine whether I'm logged in on certain sites. It then automatically navigates to the login page and, once my browser has auto-filled the fields, signs me in.