Smarter Every Day has posted a very nice example video of audio master Gordon McGladdery recording audio to be incorporated into slow motion footage. Since recording real slow motion sound that is usable at super high speeds is an impossibility due to the undiscernable pitch that results from it, you need to get creative with some reverb, echo, pitch, and chamber audio effects in order to get a compelling final product. We are big fans of both their channels and make sure you check them out for supporting them.
Video ramping is not new, it is actually been here for quite a few years in cameras and widely accessible in modern video editors. The problem is that it is still a hard thing to do properly. You either get choppy results, artifacts or pretty amazing ones by chance or by sheer trial and error and are not easily repeatable. This is where Speedramp by Prolost.com comes in!
After effects has had Time Remapping for a few years in the CS releases including Premiere Pro; but as with almost any built in feature in software it is hardly polished as well as it could be. Speedramp builds on top of the Adobe Time Remapping by incorporating a simple to use workflow that is capable of being tweaked and altered by simple parameters until you get the desired effect.