Streak is a command-line productivity tool based around the "Seinfeld method"

	[Seinfeld] revealed a unique calendar system he uses to pressure
	himself to write. Here's how it works.

	He told me to get a big wall calendar that has a whole year on one page
	and hang it on a prominent wall. The next step was to get a big red
	magic marker.

	He said for each day that I do my task of writing, I get to put a big
	red X over that day. "After a few days you'll have a chain. Just keep
	at it and the chain will grow longer every day. You'll like seeing that
	chain, especially when you get a few weeks under your belt. Your only
	job next is to not break the chain."

	"Don't break the chain," he said again for emphasis.

	http://lifehacker.com/281626/jerry-seinfelds-productivity-secret

Streak uses the Google Calendar API to maintain a calendar named "Streaks"
(that you must create yourself). The calendar consists of multi-day entries
titled "Streak" that are created, extended, or shortened by this tool.  The
idea is that you run this tool every day whenever you've done the thing that
you're trying to push yourself to do. Then whenever you look at your Google
Calendar you'll see your streaks and feel proud/ashamed of yourself.

Sample invocations:

	streak
		Add today to a streak (or create a streak if none exists).
	streak -remove
		Remove today from a streak.
	streak -offset -1
		Add yesterday to a streak (or create if none exists).
	streak -offset -1 -remove
		Remove yesterday from a streak

Andrew Gerrand <adg@golang.org>