not necessarily obscure or weird, but something kinda far out and useful:
Take an audio clip on a track, such as a vocal, guitar line, synth, etc. (using this technique with drums is very 80s sounding, be warned)

Put a heavy reverb on the track. Don't put a send to a reverb, actually put it on the track. Make it 100% wet and as crazy or not as you want.

Then, reverse the audio clip with a reverse effect. (All DAWs can do this)

Then, freeze and flatten the track (as ableton would put it), or commit the clip.

This will leave you with the reversed clip with the reverb committed onto it.

Then, reverse that new clip, so you get the original audio. Now, the reverb will be reversed on the clip! This creates something called the 'ghost' effect, and you hear it a lot in mainstream pop music. Especially when you're coming out of a breakdown or entering a chorus. But I add this here not to recommend you use it in the conventional way... try it on guitars, drums, bass. Hell, try it on a whole track! Play around with it, could be fun!