Some (read: many) programs do not support auto save.
Saver will save your work at a given interval (in minutes), you only have to specify when and give the application title (if you don't, the program saves your work in the current application). You can also specify a custom hotkey to send instead of Ctrl+S.
Download
http://www.softpedia.com/get/Office-...ls/Saver.shtml