Some time ago I got a Raspberry Pi microcomputer (an older Model B) from Amazon and an Adafruit Pi Plate with a 16x2 character LCD. This has a 700 MHz single-core CPU with 512MB SDRAM and runs the Linux OS. The Gen2 Raspberry Pi has a 900 MHz quad-core CPU with 1024MB SDRAM – a definite step up in processing power for the same price. The Gen3 version has a 1.2GHz 64-bit quad-core ARMv8 CPU, built-in 802.11b/g/n wireless LAN, Bluetooth 4.1, and BLE. But wait - there's more! The Gen4 version has a 1.4GHz 64-bit quad-core ARMv8 CPU, built-in dual-band 802.11b/g/n/ac wireless LAN, Bluetooth 4.2/BLE and faster Ethernet - same price!
A lot of folks use the Python language for programming on a Raspberry Pi. A good way to learn Python can be found here or here.
It's easy to set up and once initialized you no longer need a keyboard, mouse, or monitor.
Just plug in a 1.0 to 2.5 Ah cellphone charger depending on your model and ssh to it from another computer!
I haven't decided what to do with it yet. But they're so inexpensive that I could get several
for different projects. Thinking about a NAS server using an external hard drive,
a Stratum 1 NTP time server,
or perhaps a digipeater for APRS.
Other hams have turned these into D-STAR hotspots.
See tips at Western D-STAR and
Charlotte D-STAR.
Also take a look at NW Digital Radio,
and this UHF radio that interfaces with the Raspberry Pi.
Here's a low power 20m transmitter for
WSPR!
You could also set up a Raspberry Pi as a mesh node or an EMCOMM email server.