what is this stuff

[sonofkrono]

hey everyone, ummm.........today there were TINY tiny tiny little white piece of white that were squiggling around on my glass. also before noticing these there were about 10 or these little white sacks that looked like spider sacks do(when they lay their eggs) what are these things??? also before putting carbon into the empty cartridges in my filter there was a HUGE one of these "shells" about 3 inches by 4 inches, what is it??? sorry no pic, can't figure out how to take pics through glass.

 

[elfdoctors]

The tiny white things are probably pods - completely harmless and probably beneficial (and to be desired if you are trying to raise certain types of fish which feed on them).
The smaller cocoon like structures are probably q-tip sponges. Do a search on these boards and you should be able to find a picture to see if this is what you have.
The larger cocoon like structure might be from certain fish. Most wrasse make such a cocoon every night in which to sleep. It is discarded in the morning. It is hard to guess anything else for the large one without seeing a picture.