SMPlayer open source media player goes portable
SMPlayer Portable supports all the same media formats as the classic version. The major difference is that you can install it to a USB flash drive for use on any computer. The portable application is based on SMPlayer 0.6.2, which is the latest version. It lacks the icon themes included in the full version, and it won't write anything to your Windows Registry. You can find a complete list of differences between SMPlayer and SMPlayer Portable in the user forums.
[via The Portable Freeware Collection]