Canvas 3D Graph is a special type of bar graph that plot numbers in 3D.
Moochart is a plugin for MooTools 1.2 that draws bubble diagrams on the canvas tag. Future versions might include pie, bar & line graphs.
TufteGraph allows configuration by dynamic functions, allowing for a really compact API, and uses a non-core layout is done via CSS rather than code.
ProtoChart is an opensource library using Prototype and Canvas to create good looking charts. This library is highly motivated by Flot, Flotr and PlotKit libraries.
Protovis composes custom views of data with simple marks such as bars and dots. Unlike low-level graphics libraries that quickly become tedious for visualization, Protovis defines marks through dynamic properties that encode data, allowing inheritance, scales and layouts to simplify construction.