Lego and Stikfas toys allow film makers the ability to skip over the puppet making process for instant gratification. This is one area of stop motion animation that is really starting to explode on the internet and it's one of the most basic forms of the art.
Almost no artistic experience is needed. With the inexpensive digital web cam's and software, anyone can make a film of their own. In most cases where a film maker uses these kinds of toys, they will modify or customize them. This can involve popping one Lego mini-figure head off and placing it on another body.
Some people will print out small mouths on clear plastic adhesive labels to make Lego toys appear to talk. And some people will completely re-paint these figures for a very personalized appearance.
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Stikfas are customized in several ways. One particular way is to just mix and match different colored parts with different kits in the same way as Legos. The other is to use fine paint brushes to paint faces on their heads, pockets on their chests and belts around the waist area. Some of the more fun custom jobs I've seen were ones where people use strands of wire or string for hair, and Sculpey polymer clay built up to add muscles and details that you won't normally get when you open a brand new boxed Stikfas kit.
For animating purposes, 3mm magnets can be inserted into the square hole sockets in the feet of the Stikfas. This allows you to balance your Stikfas and keep it from falling over if it is on one leg, as long as it's on a metal surface. Metal Altoid cans and cookie tins work great for making a small set floor base just for this purpose.