We should put a hundred of these creatures into a shopping mall.

This is a disaster.
Helium resources are pretty much finite. Every time some grotty little child releases a helium balloon, we lose more of it to Space. Please stop making stuff like this!

Ha ha...
Then they could make the next part of JAWS movie series

This is wonderful! These could be mounted with cameras for surveillance, and do a lot of things, besides also being lots of fun! And for Lawrence Smallman who is scared of Helium being depleted, this is for you: as soon as Natural Gas is depleted, so will Helium, so there isn\'t much to worry about (natural gas contains about 7 percent Helium).

Its very nice, however not exactly an ideal use of helium... Same with those bloody blimps...
@chinna Helium is finite... like u mentioned, its refined from natural gas which just has 7% of it, and unlike most gas, it is unrecoverable once you release it in the air...

Trippy - really trippy. I'd hate to be doing acid and have one of these sharks cruise into the kind of dark room. Too much. Except for the really really stupid waste of helium, it's a great idea tho. Should go back to hydrogen and oxygen mixes... That would REALLY frighten them.

A company called Festo kicked this off a few years ago with a life-sized underwater penguin robot and also air penguins and jellyfish, which they exhibited at the Royal Society Summer Science exhibition in London in 2010 - very cool!

@Smallman: time to invest in Helium futures, 5 year contracts. The price will begin to skyrocket when helium production starts to reduce supply vs. demand. The major source of helium is natural gas, but storage seems to be the problem:

\"The Future
In 1996, the United States government proposed that the government-funded storage program for helium be halted. This has many scientists worried. They point out that helium is essentially a waste product of natural gas processing, and without a government storage facility, most of the helium will simply be vented into the atmosphere, where it will escape into space and be lost forever. Some scientists predict that if this happens, the known reserves of helium on Earth may be depleted by the year 2015.
Through 2004-2006, both helium consumption and the costs of producing helium increased. In the 2002 to 2007 period helium prices doubled, and during 2008 alone the major suppliers raised prices about 50%.\" Various internet sources, incl Wikipedia.

All it needed was the them from Jaws playing at the elevator door before it opened. Bet that would have made that step back more or a jump.
The reason the helium storage was even started was to have a secure source pre WW2 for airships instead of using hydrogen. And you might find that the helium used to fill one modern commercial blimp adds up to more than the helium that will be used for all of these fish being sold. And they inflate and deflate airship quite regularly for storage and transportation. You guys are complaining about burning a match when there are multiple volcanoes out there doing a wee bit more.

clever - changing: the center of gravity to get a nose up or down attitude, and then using the thrust of the tail to go up or down - very nice idea!