Info kiosk info projector
Here's one that makes good use of the RPi's other special characteristics: it's really small and physically lightweight. So hanging it on the ceiling next to a projector isn't going to cause the office Stealth & Safety crew too many sleepless nights. And yes, it's cheaper than a dedicated PC. Thanks to some decent LCD/LED projectors out there, for a number of situations it's much cheaper than, say, a 64in display screen.
Difficulty Level (1-10)
2 - Easy peasy: you're just hooking up an RPi to a projector
Extra cost
Under £500
Shopping List
Low-cost LCD/LED projector, RPi case, appropriate ironmongery for hanging projector and sticking a network point on the ceiling
Approach
The trick here is to make sure that your content will display on a hard reboot of the RPi. Setup the RPi to open a browser after booting, and make your site the homepage. Use HTTP refreshes for automatic updates.
Take it further
Add a wireless connection to the RPi to save on the cabling.
Online Help
Forums are your friend, especially when selecting a suitable projector: something that won't overheat and has a long MTBF for the lamp or equivalent.
Weather station
The RPi is ideally suited to the role of weather station: small, low cost and low power. The RPi makes a great data-logger, and you don't even need a network connection, just a large enough SD card. There tools and Python scripts out there to graph your data, or present it via a web page. And once it's up and running, you can contribute your data to shared sites like the WeatherUnderground.
Sources: Peter Mount (left) and Jim Easterbrook
Difficulty Level (1-10)
3-7 - ie. pre-built to homemade
Extra cost
Dependent on your approach
Shopping List
Dependent on your approach
Approach
GPIOs make it easy to hook it up to external sensors directly, or there are weather station boards to available to build. You can avoid a soldering iron altogether too: kits from Maplin or RS (for less than £60) that include all the basic pre-built sensors, or open source tools like Weewx let you talk to professional USB-compatible weather stations.
Take it further
A popular addition to your weather station: add a cheap web cam. Or how about a Wi-Fi or XBee connection, and solar power?
Online Help
If you thought the IKEA modders were keen, wait until you meet the Weather Station folk.
Next page: Cloud server
COMMENTS
Re: Is that it? @Jason
I get the impression you are a glass half empty type of guy. If you had spent more than 3 seconds thinking about this, you would have realised that these are just some of the projects you can do. It's not an exhaustive list! Yes, you probably could do some of them using a cheap PC, but GPIO would be a problem, as would power consumption and size.
I suggest Google, and some thought.
My project...
At the moment, I'm working on a rPI intelligent thermostat. The rPI is going to be attached to the wall next to the boiler and will handle the mains switching to switch the boiler on and off.
The thermostat itself is an Arduino with an LCD display, telling you the temp and when it's next going to switch on, also the target temp. The temperature sensing is done with an LM35 temperature sensor, at the moment it's all hooked up with USB/Serial ports (and not to the boiler, yet) but will use xbee.
The rPi runs a mysql database and the system as a whole will allow rules based heating configured from web or the thermostat, such as:
On for an hour, on all day, off for a week, minimum house temperature (frost protection), daily scheduling etc. I'll be storing all the temperatures in a database and hoping to use this more intelligently in future...
Wife acceptable
I have set up RasPBX on a Pi at home. I initially used the SPA3102 but could not get rid of the echo so I changed to an OBi110 which at about 35GBP is cheaper and much better. Now voicemails are attached to e-mails instead of hiding behind 1571, we can divert international calls straight to voicemail (as they are pretty much all nuisance sales calls) and with an additional Sipgate trunk and some Zopier soft phones we can have multiple simultaneous phone calls. Amazing for a little toy computer.
Pi-BX looks like a great little project.
My only obstacles to little projects are wife based.
Re: Is that it? @Jason
PCs are typically small or cheap but not both. The PI takes both to a new level. It's like an AppleTV or Roku in this regard. You can try to make PCs smaller but then you end up with a $1000 Steam Box or a Mac Mini. It's also nice that the PI achieves it's cheapness without being some ancient thing you retrieved from a dumpster.
Who wants their cool project to fail because it's made of parts that finally decided to die of old age?
