Transfer Iphoto files back to camera Roll iPhone 3G

Hi guys.

I've seen loads of posts on transfering files to imac, iphoto etc. Buy what about going the opposite way.

Here is my situation, I transfered a short 18 and 16 second video made with the Iphone 4s. I normally email them back later if i want to edit etc with some apps i have on my phone to send them to friends and family.

Problem is my e-mail clients are limited to the file size.

I know there is Photosync for the Iphone but it isnt free and its crazy there isnt a feature to tranfer it back.

These vidoes need to be sent to the camera roll, not the Video section through itunes. I cant load the video into the video apps I have.

Any ideas or is it Photosync or nothing?