iCloud mail is easy to set up, use and is free from Apple. For architects that want to have their own domain name as part of their email, which iCloud does not offer, one has to find another email host. This often leaves some of OS X's built-in Mail apps features unavailable. Including the new Mail Drop feature in OS X Yosemite.
Mail Drop allows attachments to be sent, up to 5GB in size regardless of your service provider's limitations, which is critical for architects that often have to email large files to clients and consultants.
For non-iCloud email accounts this feature seemed unavailable that is until Peter Cohen over at iMore posted that you can turn on Mail Drop, even for non-iCloud accounts. Check out "How to turn on Yosemite's Mail Drop feature for non-iCloud email accounts" to activate Mail Drop. Then even with your own domain email account, you too will no longer need to worry about sending those large rendering files.