3 liter homebrew beer keg

Beer kegs are several things. They are expensive, heavy, but most importantly delicious. We found a nice guide for creating your own 3 liter beer keg. This is an inexpensive solution for homebrewers looking to keg their own beer.

The guide goes into detail on assembly and parts needed to create the bottle adapter. Most of the parts can be picked up locally or through MoreBeer.com. CO2 cartridges are used to pressurize the bottle. To keep everything cool you can use a standard water cooler with a few simple modifications. The 3 liter bottle is too tall for some coolers so you’ll need to cut a hole in the lid. Add a piece of aluminum covered styrofoam to the top and bottom, toss in some ice, and your brew should stay cold for about 3 hours.

The author does note that this is not recommended for long term storage. So drink up!

RepRap universal constructor achieves self-replication

RepRap, the self-replicating universal constructor has had our attention since it first started spitting out globs of shapeless goo, but its speculative potential turned in a real benchmark recently when a RepRap machine made parts for an identical machine in a few hours (a child, in other words), then the second RepRap successfully made parts for a third or grandchild machine.

RepRap does not fully assemble copies of itself, but produces the 3D-printed plastic components necessary to assemble another copy. It has also successfully produced other plastic goods like sandals and coat hooks. [Dr. Adrian Bower] is the leader of the RepRap team, and he will be exhibiting its capabilities at this week’s Cheltenham Science Festival.

[via BoingBoing]

Gaming with Roombas

Yesterday we looked at the Pac-Man Roomba casemod. In the video, creator [Ron Tajima] expressed interest in seeing Roombas participate in real life games. So we did some digging around and found some used in an interesting augmented reality game. From Brown University, these modified Roomba Create units play various games, like tag, with an underlying goal of developing smarter robots.

The setup consists of a Java powered client/server arrangement. The game server coordinates the Small Universal Robot Vehicles (SmURVs) and builds a database of events for future use. Players can also control the robots through a Java telepresence client.

The units themselves are made up of the iRobot Create with a Mini-ITX computer strapped to the top. They run Linux and communicate over WiFi with the server and players. They also have an IR emitter used in the games to “shoot” other units.

Gameplay has the server acting as the referee and humans only acting as instructors. The humans come into play when the robots are unable to respond based on their existing database of decision making policies. Through the client, players are able to see exactly what the robot sees with the addition of 3D overlays. Future plans for the game include removing the camera view and replacing with nothing but these overlays. One of the final goals of the project was to create a 24/7/365 gaming experience similar to what is found in MMOs and Xbox Live applications today.

ARP poisoning is still a problem

You’ve no doubt heard that the site hosting Metasploit, the exploit framework, was hacked earlier this week, but what you may not have heard is that it was done using a layer 2 attack. Though Metasploit.com was not actually cracked, a server on the same VLAN was compromised and used to ARP poison the gateway. ARP poisoning is a method of sniffing data by sending a false ARP message to an Ethernet router to associate the hacker’s MAC address with a valid IP address from a genuine network node. From there the hackers were able to mount their MITM attack and show the image above instead of Metasploit’s website. This problem could have been avoided if the ISP was using fixed ARP entries, which is what [HD Moore] had to do to get the site back online. [Richard Bejtlich] points out that even though most people have been focusing on application security lately, fundamental attacks like this still happen. If you’re doing a good job protecting yourself, you can still be at the mercy of the security of 3rd parties when operating in shared hosting environments.


Chances are you’ve never wondered what your goldfish is trying to say, but if you have (or if you just want a project), check out this DIY hydrophone.

You will need a computer microphone, vegetable oil, plastic wrap, scissors, solder, and a small unused plastic bottle. Solder the mic capsule to an appropriate length of cable and test. The entire assembly can then be submerged in vegetable oil inside a plastic bottle. Yes, vegetable oil. Seal the bottle and you’re done.

DIY Slingbox

[David] took some interesting steps to put together his own Slingbox-ish setup. He used a Mac mini running Quicktime Broadcaster to capture the stream from a Firewire video camera which his cable/satellite receiver is plugged into. You’ll have to use an OS X machine, but that’s not too difficult these days. Broadcaster is about the simplest way to capture from Firewire and stream. We’re using it in our own office to multicast the signal from a Canadian satellite box.