Thomann CTM-700

It's a great accessory to keep in your gig bag (or close by if not gigging), as it can be used as a metronome or a tuner, and in multiple ways as well. When using it as a metronome, you can choose different measures and swinging styles and you can plug headphones (I imagine this could be useful for drummers as well). When tuning you can use it's internal microphone, plug you guitar or just use the provided clip-on piezo sensor. If pluging the guitar is your way, you can pass through the signal before other pedals as it has an internal buffer, but probably this will only deplete the batter faster. It has tuning modes for guitar, bass, violin, ukulele and chromatic. It is small enough to fit in any pocket as well. I think I've used it intermittently for one year before having to change the batteries.

The only let down was when I was curios to see the actual frequency of the notes on my guitar and tried to use it in chromatic mode for that, well I cannot say I'm disappointed but it would have been great to have that info displayed :)