t2 is a simple task-list web application based on the most excellent “Ruby on Rails Tutorial” by Michael Hartl, available at www.railstutorial.org/book.
I went through the tutorial, and afterwards hacked it from the Twitter-like site the tutorial builds into its current form. I make no promises as to efficiency, correctness, or (most importantly) security.
For those of you keeping score at home, note that this was done with an earlier version of the tutorial.