Don't you hate it when your automatic sprinkler system turns on in the middle of the night when it had previously rained all day? Hobbyist developer and maker Jashua became so annoyed by this he hacked together a control system for his sprinkler system utilising the Python programming language and around $US45 in parts.
The heart of the system uses an x10 controller, a cheap rain gauge, and an old Microsoft Sidewinder game controller. The system is smart enough to keep the sprinklers from turning on if there has been a significant amount of rainfall in the last 24 hours or if there is a rain forecast in the next 24 hours.
The full details along with code for the sprinker controls can be found at the source link below.