BitScope Micro

http://images.cryhavok.org/d/2481-1/You+Are+Being+Monitored.jpg

Pricerange: $ 145.00

BitScope Micro is a tiny mixed signal scope in probe but don't let the size fool you. It's a full featured mixed signal oscilloscope, test and measurement system (read full details). It's USB powered and like all BitScopes fully user programmable.

It comes with a set of ten mixed signal mini-grabber test probes and powerful software for GNU/Linux, Mac OS X, Raspberry Pi and Windows. It's the ideal diagnostic and debugging tool for any analog, digital or logic circuit, especially if you work with systems like Arduino.

BitScope Micro is a fully featured mixed signal test & measurement system. A mixed signal scope in a probe!

20 MHz Bandwidth.
40 MSps Logic Capture. (That's a bit poor performance these days)
2 Analog Scope Channels.
2 Analog Comparator channels.
6 Logic/Protocol Analyzer channels.
8 & 12 native analog sample resolution.
Decodes Serial, SPI, I2C, CAN and more.
GNU/Linux, Mac OS X, Raspberry Pi& Windows.
Built-in analog waveform & clock generators.
User programmable, C/C++, Python, VM API.
Tiny, light weight (12g) and water resistant.

http://my.bitscope.com/product/BS05/
http://www.bitscope.com/software/

And don't forget to add the price of the computer, monitor and probes.

Still this can be a very useful tool for logging and remote monitoring etc.