The bubble WILL burst. Right now retro gaming is blowing the fuck up! A boom like that almost always means a huge bust at some point. It's not an 'if' question, but rather a 'when'. If you're planning on selling, now or in the near future may be a good time. Prices WAY favor the seller at the moment.
As far as the crap that's worth .99, I'd just hold on to it or offer it in trades/lots. It's not like it can lose a lot of value, and selling it is more trouble than it's worth (for me anyway).
I.e. I don't think collecting VGs is a worthwhile long-term financial investment, like any other collectible such as comics, toys, sports cards, etc. it's like playing any market; know when to get in and to get out (if financial gain is your goal).