That's exactly what I plan on using mine for. It makes logging actions so much faster. I would love to just have a smartwatch with a set of about 12 or so buttons that correspond to a specific action, but that will take time to happen, if at all.
I think IFTTT is working on a Pebble app as well, but it hasn't launched.
Now if only it was a bit faster :( I use it to turn on the lights of a belkin wemo and it takes ~9 seconds for the light to respond, and frankly often doesn't work (in which case you get a helpful email stating it didn't work). But it's certainly much, much faster than using the Wemo app.
You can still implement this yourself using http://apps.getpebble.com/en_US/application/55123f98e28a6598... and the IFTTT Maker Channel ;)
Making it context aware is possible too (e.g. in the bathroom or at work) with some thinking of Wifi routers or if you wanted NFC tags, iBeacons.
It's also fairly cheap at $19 (though not as cheap as these Amazon buttons, of course).
Edit: Misfit Flash is an activity / fitness tracker: http://misfit.com/products/flash
[1] http://senic.com