Userscripts.org

Shows passwords on mouse hover or focus

Shows the "hover text" for some comics on the page

Puts alt text or source filename in image title attribute, if title is empty.

Translate words on a webpage from Hebrew to English and vice-versa in little tooltips

Displays the graph's value at the current cursor position

Shows "alt" attribute text in tooltips

Show character count when mouseover on textarea

Translates the selected text into a tooltip automatically. Also displays alternative translations. Based on Google Translation Tooltip MLiteKeysOn.

Displays a tooltip for YouTube videos with video information and a small player for a preview.(English/German)

Add Scripture tooltips from any online Bible to any Bible reference

Instead of an 'in reply to [someone]' link on twitter, see the actual tweet in a tooltip

Translates selected text into a ‘tooltip’ via Google translate

Expand shortened URLs (i.e. TinyURL.com, is.gd, bit.ly, etc.) wherever you go by harnessing the power of LongURL.org.

Display tooltip with movie or game info when hovering compatible links

Improves the info tooltips of thumbnails (makes them look prettier and adds further information).

Autoloads for next page of Google Images search results & Enables the images to be embeded in a preview tooltip.

Reveals destination URLs hidden by TinyURL

Auto Translate Words on a Webpage

Enables support for multiline tooltips in Firefox (works in Firefox 1.5+)

Displays Jyte claim descriptions in a tooltip when mousing over a claim.

[en-us]-> A fast way to get information about your torrent that you will download [pt-br]-> Uma forma rápida de obter informações sobre o torrent que você vai baixar

Find the meaning of any word on a

script to add the title attribute to images (based on the alt-attribute)

Reveals destination URLs hidden by snipurl( www.snipurl.com)

this script does some modifications on 4fuckr.com as you hover the picture thumbnails on the site you will see them in a full size tooltip

Adds tooltip for references to Slashdot articles

Displays info tooltips on the thumbnail images on pixiv.

Converts specific text strings to links to the corresponding pages with preview tooltips.

Forces display of tooltip previews in vBulletin thread lists, even if the original poster attempted to obsfucate their content by eg. wrapping it in quote BBCode.

Sets email subject and snippet tooltips.