http://www.zamzar.com - Free online file conversion!
this page is the best
ever wanted to convert files, but u cant find the right software???
well this page has it all! just upload your file, choose what format u want it to be and type in your mail. after just a couple of minutes u should have a email from zamzar with your converted file included.
you can also convert url's, so u can for example download youtube videos as avi file!!!
this worked really fine for me and i really love converting stuff to 3gp and put it on my cellphone. ive converted loads of files, and no virus so far
BTW. if youre using hotmail, there is a chanse that zamzars mail is put in the trash can.