HT4106: iPad: Using iPad Camera Connector with unsupported USB devicesLearn about iPad: Using iPad Camera Connector with unsupported USB devices
GIve those videos a name of exactly 8 characters, 123Movie.mp4 for example. Put those files in a folder named DCIM. Hook it up to your iPad.
There are a couple of catches. You cannot see the names of your files, you may/may not see thumbnails beyond black boxes (mine all show up as black boxes but I'm not sure if that's the issue or if it's simply because the first frame is black), and you cannot preview, you have to import the file into your iPad. Once it's there, tap open in your photos app, that'll bring up your video app and it'll play. So to view those files you have to have room on your device to import them. Once you're done, just delete them to free the space back up.