seedimages

I'm looking for a seed / plant to use in a video art experiment. I want it to basically grow like this Irish Moss cluster that I did -
http://files.getdropbox.com/u/455762/ex_irish_moss.jpg
http://files.getdropbox.com/u/455762/ex ... moss_2.JPG

Notice the size of the sprouts in relation to the quarter, super small. Way smaller then most herbs, flowers, and other common seeds.

The catch is that I can't use Irish Moss because it's too expensive for the amount of bulk I need. I need to cover large areas with heavy density (like hundreds of square feet). Any ideas for a cheaper alternative???

In summary the criteria is as follows - cheap tiny seeds that produce teeny tiny sprouts.

People have suggested salvia columbariae (chia pet seeds) which are nice but produce too large of sprouts. The seeds of Irish Moss are basically smaller then grains of sand and the sprouts are super small too.

Any ideas would be helpful, I'm at a loss and NEED the help! THANK YOU!!!