As part of my verilog exploration, I'm also going to look try to just use the open source tools available for the verilog design chain. Project IceStorm is a Verilog to bitstream flow for Lattice iCE40 FPGAs. For simulation I'm going to use Icarus Verilog. Like so many open source tools, documentation could be better. I've not had a good experience in the past using open source tools for FPGA design, but hopefully these tools work out well.