They all look like sea anemones, snowy, particularly the 1st, as all show indications of tentacles; not enough to say which kinds I fear, but if you say where they're from one might make suggestions. From the substrate (ie background) they appear to be unattached, which anemones sometimes do; so the 'open bit' with the tentacles is at 1 end & 'sucker' bit at the other end (correct me if this doesn't fit)
Ah, sorry! I live in Singapore, so these are all found in the region of south east asia. Unfortunately there are no real resources for the identification of cnidarians/tunicates over here, so I'm really clueless as to what they are. /:
The first one was unattached to any substrata, but the second one (the third picture is just another shot of it) was firmly attached to a shell.