This page has a bit of information on each script that I have written.
There are also some script snippets here. These snippets are useful but not big enough to be qualified as userscripts.

This script makes real links out of wikilinks and http: links which are commented in all javascript code (NOT in the edit part, but on *.js pages and wherever there is a source tag). It also links importScript()s. A part of this script (The importScript part) has been copied from User:AoV2/importScript_links (It wasn't working, that well, so I fixed it). Also, the general idea is an extension of AoV2's script. The script is at User:Manishearth/scriptlinks.js

To install, type this code in your skin js page.

importScript('User:Manishearth/scriptlinks.js')

This script works in beta

Allows you to selectively put scripts in "Purge mode", so that they are forcibly retrieved from the server, bypassing the cache. This saves you the time and bandwidth of bypassing your entire cache and re-downloading the Wikipedia scripts and CSS.
Installation info here.

This script adds a tab that allows the user to toggle viewing the sidebar (the logo, the search box, etc.)

It also adds a "(s)" tab, which makes the current state of the sidebar the default one by using cookies.

To save the current state ("hide/show"), simply click the ("s"). Please note that the sidebar will show when editing a page.

The script is at User:Manishearth/sidebartoggle.js
DO NOT use the script in the vector skin.

To install, type this code in your skin js page.

importScript('User:Manishearth/sidebartoggle.js')

This script does not work in beta

OrphanTabs is a script that assists in de-orphaning. The script is at User:Manishearth/orphantabs.js. For more information and a complete documentation, go here. I'm developing a Java version of this, so it may soon become obsolete.

To install, type this code in your skin js page.

importScript('User:Manishearth/orphantabs.js')

This script works in beta

The amount of information any one article is the sum of all articles mentioning that page including the article itself, in all languages, including all revisions.

As I was researching on Wikipedia, I realized that there is much more information on Wikipedia, more than meets the eye. If you open Wikipedia in all languages, you realize that if you could translate it, you would have a lot more information. So I created a script, which adds a blue '(t)' next to every link on the language portlet which leads to a wiki in a language supported by Google Translate. it also adds a faint red '(t)' next to those languages not supported by Google, so that If Google adds more languages, you can still translate them.

The script is at User:Manishearth/sidebartranslinks.js

To install, type this code in your skin js page.

importScript('User:Manishearth/sidebartranslinks.js')

This script works in beta

This script allows you to use "Edit:" as a namespace. For example, if you type "Edit:Example" in the search box, it will lead you to the edit page of the page "Example", and not the search page for "Edit:Example" The script is at User:Manishearth/editns.js

To install, type this code in your skin js page.

importScript('User:Manishearth/editns.js')

This script works in beta

This script adds a patrol tab when you are viewing a page from Special:NewPages

The script is at User:Manishearth/patroltab.js

To install, type this code in your skin js page.

importScript('User:Manishearth/patroltab.js')

This script works in beta