The tiny computer board known as the Raspberry Pi has been with us for more than four years now, and we've seen several upgrades in that time. The most recent was the Raspberry Pi 3 launched in February, bringing with it Wi-Fi and Bluetooth.
Just as impressive as the compact electronics that make up the Pi are the many different ways DIY computer enthusiasts have put these machines to good use. Here are some of the best ideas we've seen so far, which you can use as inspiration for your own projects.
1. Homebrew Amazon Echo
Whether you think you can improve on Amazon's blueprint or you just happen to live outside the US, building your own Pi-powered Echo isn't too difficult - you don't get the always-on listening feature, but you can of course tailor it to suit your own needs.
2. Remote-controlled Pi tank
This impressive Pi-powered tank can be controlled remotely and is equipped with a webcam, a laser pointer and a little BB gun to attack any small enemies that come across your path. Many of the parts used here are 3D printed, making it even more impressive.
3. Smart mirror
Still using one of those normal mirrors that just reflect your face back at you? Add some Raspberry Pi magic and you can get yourself a mirror that shows the time, your upcoming appointments, the weather forecast and just about anything else you want to display.
4. Connected doorbell
Another standard bit of household kit that you can give a smart makeover to is your doorbell - there's a fair bit of coding involved, but full instructions are provided by Kishore Gaddam at Hackster for getting this up and running with the help of Windows 10.
5. R2-D2 robot
If you've got the know-how to build (or the funds to buy) an R2-D2 frame then you can use the Pi to power it, giving the Star Wars droid the ability to respond to your voice commands, recognise movement in the room and even identify you by your face.
6. Internet photo frame
Digital photo frames seem to have fallen out of fashion lately so bring them back in style with a custom-made model powered by a Raspberry Pi. As you can connect to the internet with it, you need never run out of photos to liven up your desk or your living room.
7. Security camera
Hook up a small camera and other sensors to the Pi and you've got yourself a tidy little security camera. The experts at Adafruit have put together instructions for creating a setup that you can log into remotely - it can even track temperature data over time as well.
8. PiPhone
The PiPhone isn't going to win any design awards but it's a fantastic demonstration of the power of the Pi. By adding a cellular component to the board you can make and receive calls with it - and of course the details of the design and interface are entirely up to you.
9. Custom-made media centre
The Pi is ideal for watching videos stored locally or streamed over the web, and of course you can add music and photos to the mix as well thanks to apps such as Kodi. If you want to know how it's done then our friends at TechRadar have put together a detailed guide.
10. Arcade table
While the Pi might not be able to cope with the demands of the latest and greatest video games, it's more than capable of running classic arcade games, and you can build an arcade cabinet into almost anything you like - including the furniture in your living room.
11. Personal assistant
We've already mentioned how the Pi can become a DIY Amazon Echo, but the hardware design and background AI are entirely up to you - take a look at this Raspberri Personal Assistant which can answer your queries and won't ask for any wages or holidays.
12. Robot gardener
Too busy to water your plants yourself? Going away for a couple of weeks? You can connect up a Raspberry Pi to a pump and a weather forecast service to automatically refresh your plants when they need it most. There's a detailed guide at TechRadar.
13. Game Boy emulator
Plenty of amateur hackers have put a Pi to good use as a retro gaming machine and the latest we've seen is the Game Boy Zero: it uses a tweaked Game Boy chassis, a Pi and a modded cartridge to allow you to play games from the Game Boy, NES and SNES.
14. Talking kid's toy
As well as building new gadgets from scratch with the Pi, you can adapt existing ones, as Grant Gibson did with the Chatter Telephone from Fisher Price: he modded the toy using a Pi so it could give more intelligent answers pulled from various online databases.
15. Smart night light
There are all kinds of apps and devices out there to help you track your sleep but you can use a Pi to build your own - this effort is called WeggUp and it can be configured over the web to help you doze off easily in the evening and wake up more naturally the next day.
16. Trail camera
The wildlife at the bottom of your garden might bolt off whenever you appear, but they won't be as spooked by a Pi that's discreetly recording them. A setup like this gives you a closer look at the animals near your home and there are lots of ways of approaching it.
