Windows 7 Tip: 
SendAlong is a new web service which allows you to send more than 10Mb, in fact 100Mb on a free SendAlong account. To start out, simply fill in the email addresses of the recipients, much as you would using your regular mail client, jot down a message and choose which files you want to send. Finally, hit send. It has a free 15 days trial, after that you can buy some of the best packages from there.
Plans start at $10 a month for 2GB of upload bandwidth and 5 downloads per file. 15GB a month will set you back $54 a month.
You have also another service named Nextsend on http://www.nextsend.com/ . Very serious and professionnal
A great new site is http://www.2large2email.com , it has just launched and is easy to use. They have free accounts that let you use all featues. It looks to be a good option for sending large files that are too big to attach to emails.