To assist in my electronic endeavours I have treated myself to the very wonderful Rigol DS1054Z digital storage oscilloscope and BLIMEY, it is good. This machine does everything from FFT analysis to SPI bus decoding in realtime (almost). It's a four-channel scope, brilliant for watching the channels of something like an SPI or I2C bus.
So naturally the first thing I'd want to connect up was my modular synth. Here's the MakeNoise DPO oscillator outputs running in hard sync mode. FFT shows the harmonics and already I can see that I need to turn up the sweep extent trimpots for the pulse width modulation on two of my other oscillators.
The scope has LAN connectivity, PNG waveform saving to USB memory stick, hundreds of features you might normally expect to pay twice the asking price for.
And by illicitly googling "RIGLOL" you can find a page that lets you enable the paid performances for free.
Not that I condone such behaviour.