We all get them and we're all annoyed as we sit there waiting for our email to un-clog as we wait for some 20 MB attachment to download.
So stop sending them! There are plenty of good free options for uploading your files to the web and emailing a link instead.
This is a tool just for emailing large files. You simply upload to their server and they send the email with all the links ready to go. It's pretty simple.
This is primarily a file backup system that works with your local hard-drive, but they also have great options for creating shared folders you can post files to for others to upload.