I wanted to make an indicator that behaved similarly to Parallel Channels. This is what I currently have.
Blue Channel for uptrend. Red Channel for downtrend. Both for ranges.
Recommended periods are powers of two (16, 32, 64, 128, 256), which should be adjusted according to volatility.
There's a alternate version of this same code that shows an Oscillator instead. Less clutter if you're using more than one at once.