Glad to see that cgk had the answer to your question.
NAMBLA is despicable - never heard of SOS, but they'll be included in the description from now on. Bill O'Reilly is irritating, but he is one of the very few media 'folks' that has taken on NAMBLA.
SOS stands for 'Spirit of Stonewall' (reference post 12). As per that press release in post 12 NAMBLA is suppose to be the same as Stonewall.
What is disturbing is the member list at post 1 for the Stonewall Vets.