Imitation is the sincerest form of flattery! I'd love for others to build off of my ideas. The only price I ask is that you post pictures of the results.
Feeder tendrils: these are the insides of pipe cleaners. Just pull all the fluff off and you have great tendrils (also makes great rope for 28mm models). They're simply painted black with dots of Ice Blue.
Torpedo Krakens: these are built from a Carnifex tail
(this bit), a 'gaunt Spinefist, and the ammo sac from one of the 'Nid guns (don't remember which).
Claw Krakens: these are simply from the Harpy/Hive Crone kit. No conversion necessary other than re-posing some of the tails.
Cruisers: I've got a picture up of a cruiser that I made from a shell, with flesh hooks as Bio-Plasma. I've got some others that I don't have pics of yet that are made from
these shells. Idea is that each weapon loadout has a different shape to make them easy to tell apart.