20 great GarageBand power tips you need to know | MusicRadar:
"GarageBand’s selection of virtual pedals and amps can liven up any sound in your project. Here’s how…"
Also:
"For Software Instrument tracks, the top-right corner of the Smart Controls panel houses a button that looks a bit like the flying saucer from Space Invaders. Click this to enable a hidden, preset-based arpeggiator. A generous library of presets is accessed via an adjacent popup menu, from which you can also edit note order, rate and octave range."