I travel a lot and I like to take my media with me. However, I'm rarely end up at places with a strong internet connection and I don't like having to hook up my laptop to the TV. So a couple months ago I decided to build a portable media computer, and as a result, Mjölnir was born.
Mjölnir (so named because it looked like Thor's hammer before I painted it), is essentially a Raspberry Pi, a powered USB hub, and a portable HDD tucked inside an electronic enclosure.
The Raspberry Pi is great, especially when it's tucked away behind a monitor. However, it isn't perfect as a something to carry around with in your travels. To make it as small as possible the connections are all on different sides of the board. Plus, once you've found them all, you have to hook up the pi to a hub, the the hub back to the pi to power it, and then your portable HDD into the hub, then plug in power to the hub, HDMI into the pi, and ethernet. . . . on and on. And a crow's nest of wires does not look very good.
Mjölnir was born out of a need for simplicity. I wanted it to be just like a tiny computer, all the ports at the back, just plug things in and go.
If you follow these instructions you too can have a portable media computer for around $215.
Wow, the feedback and response to this has been incredible. Thank you to everyone that has viewed it and commented. I'm glad the majority of you like it. After recieving some feedback I'll try to clarify some points I failed to make in my instructable:
There are a lot of parts that go into Mjölnir. Here's the list:
You need to make 3 custom cables for Mjölnir, and they will all come from that random USB cable you found.USB to Fan
The USB to Fan cable is very easy.
You need something to go from the panel adapter to the USB hub. What I ended up using was a couple more inches off the USB cable you just chopped up. Here is the panel adapter that you'll be using. Basically, we're making a coupling from the outside of the case to the USB hub. The two pieces match the female and male plugs of the hub perfectly.
I couldn't use the little plastic cover on the male part that goes into the hub inside the case. It just didn't fit, so I went without and covered it in a little sugru.
I also would recommend either putting in some connectors into your power cable or waiting until the end to put it in and finish the connector because the male piece will not fit through hole you drill for the female piece that attaches to the panel.Reset Switch
The reset switch is a bit of a two-parter.
First you need to solder the headers onto Pi, then you create the cable/switch for the panel.
I didn't end up using a panel mounted switch and a custom wire for my reset switch because I had this switch left over from a previous project.
You will need holes for the power adapter, HDMI plug, Ethernet, USB, & reset switch.
I drew up a pattern for drilling that would fit my 40mmX40mm fan nicely. I put one vent on the front left (looking at the case and assuming the panel connections would be rear) and one on the rear right side to get as much cross ventilation as possible. I used a Rigid drill bit that was recommended to me at Home Depot for metal drilling and it made it through all the holes. Almost 200!
To be honest having a drill press to do this would have been nice. My holes aren't exactly in straight lines. . . but it's not terrible.
I printed off my pattern and taped it to the case where I wanted it then simply drilled through the paper, as shown in the photo.
Paint the case whatever color you want and while it's drying install your choice of XBMC on your SD Card.
After the paint has dried attach the fan to one of the vents (the front one fit best for me). I had no desire to use bolts so I stuck it to the vent with a bit of Sugru in each corner.
Then, since my reset switch wasn't designed for panel use, I attached it to it's proper hole using Sugru as well.
I added 3 pieces of Sugru to the bottom of the Pi so it doesn't rest on it's pins.
Finally, I put 4 pieces of Sugru on the bottom of case to act as little rubbery feet.
All in all I used two mini packs (5g each) of Sugru.