Share and Share Alike
Dushare makes it dead simple to take a file on your computer and share it with a friend. Visit the site, pick your file, decide if you want to password protect the download, and then share the short URL with your friend. If they can visit a website and download a file they can grab the file you're sharing. Dushare also includes a chat function so you can talk to the person you're transferring the file to while the transfer is in progress.
Dushare is a free service and requires no registration.