Nuravine is an app-controlled hydroponic growing assistant that monitors and maintains proper nutrient and pH levels through its combination of sensors and a connected app you can access from anywhere.
Blocks is a modular music-making system you can build out to include multiple modules for playing precise notes, drumming with your fingers, looping and other controls. The prices start at $180 (£170) and $300 (£280) for the Lightpad and Seaboard Blocks respectively.
Project Orrca is a fully functional and programmable water filtering autonomous robot that targets chemical pollution and can be used in any body of water. Its makers are currently working on a solar-powered version for the device to increase its running time.
Joe Herman and his partner have created a way to cheaply make your own system for transferring old movies on film to 1080p digital video with old projectors found on eBay. Their project plans and advice are free here.
Audtra is the "first social audio/transcription and analytics platform." Basically you can dictate tweets, podcasts, or anything you'll want text of and post it to a timeline. Audtra is available on the Google Play and iTunes stores now.