We’ve all decided that a wiki would be an efficient way to communicate information to everyone in the house. For example, when is the water bill due? Check the wiki. Who do we contact about the trash pickup which never seems to come? Check the wiki.
This life-hack question reminds me of Cheryl Geisler's research into the use of technologies for managing home-life (here and here). It's my home-life texts that I have the most trouble tracking (especially due to nearly annual moves). Electronic banking and bill-pay has cut down on the negative effects of this, but remember how complicated it can be with multiple roommates.