Question
I have a two inch long black fuzzy caterpillar with red rings at each joint. He likes to craw around my garage floor during the day. At night he goes out and feeds on grass.  When I pick him up he goes into a tight round ball. What do I have?  Can I do anything to help?

Answer
There are thousands of caterpillars and these are Identified by what they feed on and the location. A picture and where you are located would help. But without these I would take a guess that it is a Eyed Tiger moth. The caterpillar is mostly black with tufts of stiff black hairs of equal length radiating around its body. Rolls up head to tail when disturbed. When curled, red intersegmental rings are visible between the hairs. Hypercompe scribonia - Giant Leopard Moth

Here is a web link to a picture of this caterpillar.
http://davesgarden.com/guides/bf/showimage/2848/