I'm currently using Freedom of Movement on my SCM/Cleric as his Contingency.
Heart of Water has that covered nicely for me.
If I'm not silenced, I can also always Teleport, and if I am silenced, I have a 6d6 Fiery Burst. I completely forgot to pick up Shrink Item when I made the character, I'm going to have to try to track that down now, cause the options it provides are far too hilarious to miss.
I think "unable to act" has promise, but I don't want to be teleporting to the hinterlands just because I ended up stunned for a round. I think I'll go with "cure wounds, if damage would otherwise cause me to fall unconscious" for now, and I'll work on finding wording for "unable to act" for when Teleport becomes an option.
So hey... the contingent spell must "be of a spell level no higher than one-third your caster level." Can you apply metamagic to it? If so, does it raise the spell level for contingency purposes? I might as well Maximize the cure wounds if that is a legal option...