Yeah, the $1 DLC idea has come up a few times, either for establishing ownership (might work?) or for allowing trading cards to drop (absolutely can't work), but I'm hesitant to do either. (That's something Valve really needs to address from their end by giving players the option to choose whether free games should be owned by the account when installed.)
In any case, if you send me an email (jpittman at gmail dot com), I can give you a Steam key for YHtWtG which should have the same effect.