Last night at ETech, Make magazine sponsored a "Make Fest" where hardware hackers showed off their stuff, from simple DIY paper planner mashups to really complicated projects like cramming a Windows machine into an old Atari console. Here are some of the highlights from the evening.

Make editor in chief and BoingBoing founder Mark Frauenfelder shows how to make prints using the "Print Gocco" silkscreening kit.

Make associate editor and inveterate hardware hacker Phillip Torrone shows off the latest Roomba vacuum cleaners, which come with serial ports. Plug in a serial-to-Bluetooth adapter, as shown in the closeup shot here, and you can control your Roomba remotely via cell phone or laptop. Torrone hosted a "Roomba cockfight" later in the evening that attracted a rowdy, noisy crowd.

Hardware designer Joe Grand, of Grand Idea Studio, boots up a Windows PC that he's crammed into the shell of an old Atari video game console.

UCSD researcher Natalie Jeremijenko with some of her robotic waterfowl. She gets kids with remote controls to send these robot birds in the midst of real geese, where the robots can interact with the birds, enabling the kids to learn how to "speak goose" by responding appropriately. More details at her Ooz Project. She also has a cool site, How Stuff Is Made, which has more than a hundred visual essays created by her design students showing how various consumer products are manufactured, from American flags to fortune cookies.

Syuzi Pakhchyan, a design student, showed off garments and jewelry she's created that use zippers, snaps, and conductive velcro to complete electronic circuits, causing various things to light up or change color. Shown here: A hoodie with a luminescent display on the back, which lights up when you pull the hood's drawstring.

Your correspondent Dylan Tweney shows how to use a PVC pipe mini-marshmallow shooter to achieve maximum range (30 feet or more) with just breath power. Later in evening several marshmallow shooter battles broke out. Among others, tech pundit Esther Dyson was seen gleefully firing off volleys of marshmallows at other attendees. At the end of the night, the hotel's carpet was dotted with sticky spots of squished sugar treats.