Lost Colony: Not played straight, for the most part, simply because with the stargate network, virtually every system is visited on at least an infrequent basis (for routine maintenance checks, if nothing else) and/or receives at least basic extranet service, so most colonies would never have a chance to get lost.  Abandoned colonies, hermit colonies, and lost castaways of distinctly sub-colonial size – although even this last are rare – now those, we can do you.