Secure file transfer

[u.bodalina () gmail com]

Hi All
Are there any good solutions for secure file transfer in a corporate environment. 
This should also cater for:
1. Secure transferring of large files which cannot be emailed. 
2. Allow the tranfer of these files to people on the internet.
3. There should be very little administration of accounts.
4. It should be assumed that the files are of a sensitive nature.
What are the best practices for this and the security implications?
Thanks in advance.