Second Life Viewers ➩ The Dolphin Viewer

"The Dolphin Viewer is a viewer for virtual worlds, based on the official Linden Lab source code, that contains many fixes and enhancements for builders, explorers, sailors, and other vehicle enthusiasts. There are versions based on Snowglobe 1.5, on the official Second Life Viewer 2, and on the official Second Life 3 source code with mesh support"