To generally screw with your weekend, it's time for the Semi-Annual Viaduct inspection and closure. The viaduct will be closed Saturday and Sunday from 6:00 a.m. to 6:00 p.m. On the bright side, if you have an old "Official Bikini Inspector" t-shirt and you write "viaduct" in Sharpie over the word "Bikini," you could spend the weekend hanging out with Department of Transportation officials.

Friday:

For a sneak peek at what our future robot overlords will look like, attend the free FIRST Robotics competition. This event combines sports, games, and remote-controlled robots, plus you can take a self-guided tour of the "Robot Pit" (wear closed-toed shoes because of potential ROBOT DANGER)! (Key Arena, Friday and Saturday, 9:00 a.m. to 4:00 p.m., free)

Saturday:

Day two of ROBOT OVERLORD OLYMPICS. See Friday entry for details. (Key Arena, Saturday, 9:00 a.m. to 4:00 p.m., free)

Believe it or not, something Scandinavian is happening in Ballard! Saturday celebrates a Taste of Norway and Norwegian Cultural and Heritage Day. A "Leif to Leif" 5K "fun run" starts at 9 a.m., followed by everything from a pickled herring taste-off to Rosemaling, bunad, krumkake, smørbrød, ertesupp, rømmegrøt, Leikarringen, and leksvik. If you can tell which of those words is NOT Norwegian and is actually stolen from an Ikea catalog, this event's for you. (Saturday, Leif Erikson Hall, 2245 N.W. 57th Street, 10.a.m. to 4:00 p.m., free)

If you missed the Seattle Tilth edible plant sale last weekend, they're having a Second Chance Edible Plant sale on Saturday. These are the leftovers from last weekend, discounted 40-60 percent. Veggies for $1.50 and herbs for $2.00! Fruiting vines! It is a scientific fact that a homemade dinner with food you grew in your garden will get you laid. (4649 Sunnyside Avenue N., behind the Good Shepherd Center in Wallingford, 2:00 p.m. to 4:00 p.m.)

Also on Saturday, celebrate Earth Hour from 8:30 p.m. to 9:30 p.m. with the city by shutting off non-essential lighting. Expect darkened municipal buildings downtown, as well as Space Needle and Key arena. World Wildlife Fund is promoting this nation-wide event to raise awareness of climate change. (City wide, 8:30 p.m. to 9:30 p.m.)

Sunday:

Even better than a Stitch-and-bitch is Mend & Measure, a free class on how to fix your debilitated clothes. The ladies from Blackbird clothing shop will teach you how to sew on buttons, mend your jeans, or replace the zipper in those pants you used to love. Mending supplies will be brought by the instructors, but bring your own if you have them (and bring the stuff you want to mend, duh). Ladies are welcome even though Blackbird is a shop for dudes. (Sunday, the Field House, 5465 Leary Ave. N.W., 3:00 p.m., free)