Most amazing/interesting aquatic creature

[HAZ]

I have been keeping aquatic life for a years and my weekend hobby has become fascination. I generally keep animals which have interesting adaptations which they use to survive in the wild eg. Archer fish. I have been scouring the web for a new "amazing fish". I am willing to use a very large tank if necessary. So what do you think the most fascinating aquatic creature is (preferably available in the aquarium trade)?

Thank you, Harry

 

[spotfin]

freshwater: South American stingrays
saltwater: frogfish

 

[alcohologist]

you could look around for some flashlight or pinecone fish. dont know what would be easily obtained in Australia, but ive seen a few pinecones here in singapore.
you could also try remoras, or sharksuckers. they'd need a big tank but then think of all the cool tankmates they could have... haha.

 

[Mantis411]

a mantis srhimp, they aren't a fish but i find them very interesting

 

[DJC776]

Stone fish

 

[thefishofdoom]

ya i would say mantis shrimp there an awesome creature

 

[Scuba Kid]

Octopus.

 

[davo]

cuttlefish, octos, mudskippers, soles/flounders/rays... any electric fishes

 

[convict94]

get a honeycomb or a zebra moray eel!! they are the coolest things i have ever seen i swear!!!

 

[HAZ]

Thanks for all the suggestions everyone keep them coming. I want to keep them all!