If weapons are your thing, then Armory island may be worth adding to your landmark list. It’s owned by Australian Apollo Case. Apollo describes his island thus:

“Armory Island is Second Life’s largest virtual arms area with almost fifty independent exhibitors. There is a broad range of weapons, shields, clothing and gadgets for every avatar”.

An example of what’s on offer can be seen here:

Armory Island even has a motto: “Come for the guns, stay for the fun”

Check it out in-world