ImageShack provides free image hosting with unlimited uploads and bandwidth. Their only limit is the 1.5 megabyte filesize restriction for uploads. Photobucket was the dominant image host for over a year, but in 2006 ImageShack has surged in use and popularity.

This could partly be due to the fact that ImageShack does not require a registration for uploading and hosting images, and sets an extremely high limit for the amount of bandwidth each image may consume. Photobucket's strict limits caused a lot of images to either be deleted due to inactivity, or replaced with a bandwidth exceeded image due to transfer restrictions.

The downside to uploading images to ImageShack anonymously is that uploaded image URLs cannot be recovered if lost. Registering an account solves this problem by saving and organizing all uploaded images, so that you can obtain their URLs easily.

ImageShack claims that as long as an uploaded image does not violate their Terms of Service it will be available on their servers forever. As long as this promise is kept and they take careful steps to avoid catastrophic losses of data, their feature set and relative lack of limits give ImageShack a huge advantage over image hosting competition.