Where To Get Online Data Mining Work?

Where can I get some open source data to apply data mining and machine learning techniques that I have learned?

• I am really really excited about astronomy but I don't really have much of a background in its math. However, I want to contribute something to that community. I am learning some useful ways to mine patterns in large scale data. I want to know if there are any datasets or problems where this would be useful.

• Answer:

  http://www.kaggle.com/c/mdm http://www.kaggle.com/competitions Even if competitions have closed, still  most of the data will still be available.