The bee humming bird lays the smallest egg at half a gram, and the ostrich lays the biggest at 3.3lbs. The animal that lays the smallest eggs are insects but when referring to vertebrates the animal that lays the smallest egg is the hummingbird.
The smallest animal in the order Petaurus, which is an order in the possum family, is the sugar glider (Petaurus breviceps). It is not the smallest glider: that honour goes to the Feathertail glider, but the Feathertail is in the order Diprotodontia.
The smallest animal that you can see is a Megaphragma caribea, also known as the Fairy fly. The fastest animal on earth by flying is the Spine-tailed Swift (106mph).The fastest animal on land is the Cheetah (70mph). I hope I helped! :-)