The daylight detectors and comparitors that I mentioned only yesterday are already available for testing with the release of this latest Minecraft snapshot, which goes by the catchy name of 13w01a. It's a significant update, too, adding the new hopper block, a chest that gives off a redstone signal when it's opened, nether ore and nether bricks. You can find your copy waiting very patiently for you on their blog.
UPDATE: After some bugs surfaced, Mojang have now released an update to this snapshot. Don't worry about yesterday's release and instead be sure you get the newest one here.
Here's Mojang's not-quite-exhaustive list of what you can find in this snapshot:
- Redstone circuits are more consistent and pistons should be more stable.
- Added the redstone Comparator block (this replaces the capacitor mentioned at Minecon).
- Added the Daylight Detector block.
- Added a Hopper block (still work in progress).
- Added a chest that activates redstone.
- Added weighted pressure plates that detect item stacks.
- Added redstone block (works as a pushable redstone torch).
- Added a new ore to the Nether.
- Added a Nether Brick item for crafting Nether Brick blocks.
- A whole bunch of other stuff... Try for instance double-clicking items, or drag-placing them, in the inventory.
If you're trying out a Minecraft snapshot for the first time, we have a guide designed specifically to help folks like you, just over there in the corner. Go on, give it a go.