Can't afford a Raspbery Pi ($35), well they have a competitor now. The ultra cheap CHIP; a 1GHz processor, 512MB RAM, with 4GB storage, WiFi, Bluetooth, support for most monitors and even a mobile capacity. It runs Linux and therefore supports many free productivity apps. As you can see from the picture it's very small and so can be easily embedded in pieces of equipment. CHIP is a Kick Starter project and be honest for just $9 (US) can you not afford to own one.