Since the great introduction of short URL services such as bit.ly, tiny.url etc  to shorten long urls, there have been reports of abuse whereby spammers, virus and malware creators use the service to to victimise others.

Just recently, both Twitter and Bit.ly have taken measures to prevent the spread of malwares by scanning all submitted, shortened and shared URLs in order to protect users.

However, you may want to uncover, unhide and expand these URL before clicking them. Performing this simple task could save you a lot of money if a link contained a malware. Below is a list of services that I have been using to scan shortened URLs against virus:

• ExpandMyURL.com
• Untiny.com
• LongUrlPlease.com
• URLvoid.com
  

For Firefox and Wyzo users, there are add-on's:

• LongUrlPlease add-on
• LongURL Mobile Expander add-on
• Open Long Url add-on
• PowerTwitter add-on
• Bit.ly addd-on (works only with shortened bit.ly links).