Ow.ly - Shorten links, measure traffic, and demonstrate social ROI right inside the Hootsuite dashboard.
ThirstyAffiliates - The Best Affiliate Link Cloaking Plugin for WordPress
YOURLS - YOURLS is a website that contains all the tools you need to create and launch your very own URL shortener. URL shorteners like bitly or TinyURL are fine for public use, but they offer limited options in terms of URL customization.
Pretty Links - The easy way to customize Facebook link previews
Polr - An open source URL shortener. A great non-profit and free alternative to bit.ly, TinyURL, or goo.gl.
Affilimate - Track your affiliate links and commissions in a single dashboard and increase revenue with a data-driven strategy.