Identification: yellow mushrooms

i recently repoted some on my houseplants with some new dirt and bigger pots. A few weeks later there was this yellow alyer across the dirt. then a week later they were big yellow mushrooms, pretty brghtly colored too. what are they?

 

looky here:

http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=17336

http://mushroomexpert.com/leucocoprinus_birnbaumii.html

 

hahhah thats awsome... and fast thanks man

 

hey id love to see a pic of your fungi