From Expert Sleepers:
Augustus Loop is an emulation of a tape-based delay effect, with some extra features to facilitate its use as a looping device. The key features of Augustus Loop that make it more than just a big delay effect are: Really long maximum delay (3600 seconds that's one hour). Tap length/tap record. You can set the loop delay time while recording your first phrase. Virtual tape. The delay simulates an old-style tape delay, meaning you can --change the tape speed (i.e. pitch up and down) --reverse the tape direction --smoothly change the delay time (as if you were changing the head gap on a tape delay). Multimode filter and saturation in the feedback loop. Four feedback taps (left to left, left to right, right to left and right to right) with independent delay time and feedback settings, for ping-pong effects, stereo delays etc. Pitch and filter LFOs. Loop length can be set in terms of the host's tempo setting. The plug-in can output MIDI clock messages to synchronise other applications to its loop.