Picked up some frags, and got lots of hitchhikers...What are these?

[Myka]

That starfish is no Asterina. I'm not sure what starfish that is, but I wouldn't trust it since most starfish are either not reef-safe or not sandbed safe.

So...if these things are all alive I'm assuming you did not quarantine or dip the corals before placing them into your tank? If that's the case, I would strongly suggest that if you aren't going to quarantine the corals that you at least start using a good coral dip to "wash" the corals of any hitchhikers that might be catching a ride. There are many hitchhikers that would cause a lot of grief. I really like CoralRx as a dip, and am not a fan or the iodine-based dips.

[Aquaria]

Unless u know ur coral is coming from a pest free tank I highly recommend coralfx as well its great stuff. Saved me from adding flatworms montipora nudibrachs etc.