Studio bods love compressors, but for guitarists they're often overlooked.
Use it wrong and it can destroy your sound, but use it correctly, and you'll reap the benefits of sustain for days, punchier picking and substantial boosts.
We like the Vise Grip, because where other pedals can squash your sound out of shape, the Vise Grip's blend control and frequency switch allow you to mix your dry signal (or just the dry highs or mids) with the compressed sound.