How do I make a custom block that has an image background with hotspots? I am working on making a custom module with a block that contains a floor plan.  It will be an office, when you hover over employees desks it will have a bubble appear showing that employees project status and other information.  All instructions I can find for setting the image in the block uses css.  Is this how I need to do it? Will i be able to set regions for mouse over this way?
You can try the module jQuery Map Hilight which uses jQuery maphilight plugin (visit the link to view demos).

Download from David Lynch blog / GitHub.