For me I use DivShare but Im open-minded to anything faster, cleaner (website), simpler, or just better.
Windows Live SkyDrive, I like it's "drag&drop" upLoad plug-in and the 5gig capacity. Has a 50meg file limit though...
I just found http://www.fast-load.net , which seems to be quite good - 5x250MB per hour at full speed for free, unlike rapidshare with 100MB per 2 houres.
Other . I don't use such services . I have my own account to load files on my ISP's FTP server with 20 MB limit (almost full) . Very clear (no adds) and fast site you can try is http://4storing.com/ It is in Bulgarian but I guess the language is no problem , very intuitive , just click there , click Browse , load the file and you'll get a link to share. It allows you load file which is up to 1.5 Gb in size. The site offers premium services , but the free aren't bad , too
I have two main favourites: Livedrive and Mediafire Pro. I also like the concept of Wuala as social storage.