Drawasaurus - Drawasaurus is an online drawing & guessing game you can play with friends or strangers.
LetsDraw.It - Guess and Draw, Drawing Battle, Pictionary, Copy picture - online drawing games where you can compare your skill with others.
Sketcharama - Draw a given word and let the other players guess your sketch.
Drawaria.online - Drawaria.
Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
SketchParty TV - SketchParty TV is a high-tech drawing game that plays a bit like Pictionary.