Seed is probably best thought of as an single-address-space, linear-object-based, native, persistent operating system with event-based pre-emptive-multitasking, but without anything resembling a traditional kernel or filesystem.
kissme is a free (GPLed) Java Virtual Machine. It is being developed on GNU/Linux and can run console java applications. kissme is to be used with the GNU Classpath java class library. kissme also provides support for orthogonally persistent java.
Why do it the tradidtional way when you can do it a new way? Why use an existing wheel when you can reinvent it yourself? Why do it the easy way when a hard was exists? Why? Because we are professional geeks!