You get to create a Short URL for your email address that you can share with others. A captcha version is required before the email address is shown to the user.

This is a good way to eliminate a substantial number of spam bots. As an example, you can get in touch with me by visiting http://scr.im/anuj

You will be presented with a captcha verification like:

Select the correct image and you will get to see my email address with options to either copy the email id to the clipboard or to compose an email via Gmail.

Post from Twitdom - scr.im

As described by the author:

Super-charge your the links you share on Twitter. Adds reference to every link you tweet and shares a link to your website and Twitter profile every time someone visits or retweets.

Post from Twitdom - TweetALink

You can create custom Short URLs also, subject to the keyword being available.

Post from Twitdom - Pie.im

You can place widgets on your site to create short URLs. An API is also available to integrate into any 3rd party application.

Post from Twitdom - Universal URL

The developers are planning on adding new features on top of the basic service. E.g., Members Area for tracking the links, etc.

Post from Twitdom - href.in

You can select your license, and programming language. Based on this it creates a short url to your code which is displayed with syntax highlighting.

Post from Twitdom - twitsrc

A bookmarklet is also provided for ease of use.

Post from Twitdom - simpl.es

Post from Twitdom - Plazz.me

Links are shortened using twurl.nl.

Post from Twitdom - Tweetburner

Post from Twitdom - In2s