I think someone has sent me stolen lindens?

[Dessicated Audion]

Somebody teleported into the sim I was at and sent me 75 lindens and said it was someone else's money, I'm not friends with them and they seem to have sent it to several different people in the sim.

[Rolig Loon]

It might indeed be stolen, but it also might be from a friendly resident who has more L$ than he knows what to do with (or maybe more holiday spirit).  The way to cover yourself, just in case, is to submit a support case (or an Abuse Report -- you decide) to Linden Lab.  Copy all information about the gift from theTransaction History on your dashboard.  Include all of that information in the support case.  If Linden Lab decides to take the money, you're not out anything, since it wasn't yours to begin with.  If they say it's OK, then you have a paper trail to protect yourself in case the surprise gifter claims that you stole money from him.   In the meanwhile, keep the L$ and wait.  Do not send it to anyone at Linden Lab.

[Lindal Kidd]

Rolig is quite correct.  And in fact, some griefers have used the fact that receivers of stolen $L can get their account put on hold at best, and deleted at worst, by Linden Lab, to get innocent people in trouble.  However, the amount you have been given, $L75, is about $0.30 in real money.  You will almost certainly not get in trouble over such a trivial amount.  LL only takes action on much more significant amounts, like, say, $L10,000.  If you had gotten a very large gift like that from a stranger, I would definitely follow Rolig's advice.  I'm not sure I would worry about just $L75.