There are many possibilities today when you would like to send a big file to a user.  IMHO, sending big files over e-mail is a big waste of bandwidth; think about it.  You send the file to the mail server, which sends it over to the recipients mail server, which is then transferred over to the recipients machine.  The file travels a lot!

It is best to send links to files you would like to download (unless you are sending small files).  For the last year I had been using streamload, but lately things have changed and it has just been awful.

I searched for a way to send big files and stumbled upon SendSpace, which lets you send files without any problems.  They offer a client for uploading files for Windows, Mac OS X, and Linux.   Furthermore, they offer some features such as notification when the file you have posted has been downloaded.  Here is snapshot of the client, make sure you check it out: