Ren makes a great first impression. It's a "universal interoperability" project that aims to allow the sending of any asset from any chain to any other chain. They have a great white paper (docs) that explains the problem in a good amount of detail that is also very good educational material on the problem itself. REN has been developing the next generation of their protocol but is currently in a funding crunch because they have been funded by an FTX subsidiary. Therefore their funding is running out in 2022 and they are looking for other options. Show Less