The problem is not exactly the size but the method and security. Right now i use two sites to do that :
First is a site where i upload my file and get link for download: http/tranzit.dir.bg/.
Second i use this one to encrypt the link and set password for the recipient for security reasons : https/urlcrypt.to/
That the way i do it now but i am not sure if that is the best way.
The problem is that i am in my office and i have to send large .dwg files to other engineers working on the project. Some of them work from home and on top of that they are 70+ years old and the use only Autocad and some basic mail client. So you see VPN tunnel here just can't happen. As till now i found that sending them links to download is the easiest way. If someone can suggest me something else. As for the encryption i do it just for safety reasons.