Logic gates

[immibis]

Logic gates (that use 1 as true and 0 as false): rykumyd (AND at top, OR at bottom, NOT at right)
But it would be easier if the presence of a crate is true, and the absence of any crate is false.
Logic gates that use any crate as true and no crate as false: fituryk (AND at top, OR at bottom, NOT at right, note the old physics).
These are very small (most of the space in each is taken up by a device to adjust timings, and a full-speed draw), and run at full speed.

[Rene]

Logic gates that use any crate as true and no crate as false: fituryk (AND at top, OR at bottom, NOT at right, note the old physics).
These are very small (most of the space in each is taken up by a device to adjust timings, and a full-speed draw), and run at full speed.

The old physics is still fun!
Things get a lot simpler if you don't care about the value of the barrels: lubiged
Left side top to bottom: OR, AND, splitter, flipflop
Right side top to bottom: NOT, switch, wire crossing
All run at full speed

And here is a working circuit with the gates: sivanic. It's a traditional SR flipflop with 2 OR gates, 2 NOT gates and a wire crossing. The stuff on the left is to generate regular set and reset pulses. You'll see some oscilating behaviour at the start - before the first reset pulse. It's funny to see the electricity flowing at 10 ticks per second...

[immibis]

Very good. I especially like your NOT gate and flipflop. What's the middle-right thing supposed to do?
You can also make a SR flipflop easily if you abuse a bug (which will not be fixed because it's actually useful) in my Rubicon (http://kevan.org/rubicon/forums/index.php?topic=308.msg3676#msg3676) where ultra-dozers can't fall down. See tenecef. The middle one oscillates between on and off quickly and controls itself (Q is connected to Reset, Q-Bar is connected to Set) while the right shows how small it can be (it oscillates based on an external input). The left side shows how to put the Q and Q-Bar outputs on one side
If you don't remember what Q and Q-Bar are, Q is the output which reflects the flipflop's state and Q-Bar is (NOT Q).