Well, the slug has whooping 32MB of RAM 😉
Oh, and more recent models of the NSLU2 are clocked at 266Mhz. But also 133Mhz are suitable for firefly. It may not be a speed demon, but it serves the purpose. And it keeps the electricity bill low 🙂
So a Geode should definitely work, since it’s x86-based and even has an FPU. 8)