Tribbles-way too cool!
 

If you are looking for something different for your foreground, try
Cladophora aegagropila. These are the algae balls discussed on the Krib
at

http://www.thekrib.com/Plants/Algae/cladophora.html

I got two from Dwight at Florida Driftwood-they are round, green, and
healthy

http://www.floridadriftwood.com/product.asp?3=552