GT-0005 XMEGA Xminilab Plug-in Mixed Signal Oscilloscope, 3.3" x 1.75" Size

This is the coolest little dual-trace 200-kHz oscilloscope around (at least for now). The breadboard design makes it ideal for circuit development and simple diagnostics. It also provides a spectrum analyzer, waveform generator, XY Mode, Meter Mode, numerous trigger options including an external trigger.While the small display is great for diagnostics on the bench software also developed by Gabotronics provides full functionality and bigger display from a PC (or MAC, Linux or Android but I haven't tried those) via the USB connection. All the controls normally accessed from the onboard menus are available from the PC scope. Even the $20 Xprotolab Plain (without a display) is supported by this software, so a full-featured oscilloscope can be developed for the price of a burger and beer.The software and manuals for these products are available on the gabotronics.com web site, without which you'll get nowhere.

I have one that I am using to learn the hardware side of things. I really love it - just today I used the UART protocol analyzer to check serial output. It is elegantly designed and has a very friently user interface.