- KiCAD: http://www.kicad-pcb.org/
- Eagle: http://www.cadsoftusa.com
Are the most popular entry level ones. You can make an ARM or i7 board with either. I think Bunnie is using Altium which is much more pricey.
- DipTrace: http://www.diptrace.com/ (probably best bang/buck in terms of capabilities/learning time)
- gEDA: http://www.geda-project.org/ (not a beginner tool)
- Fritzing: http://fritzing.org/download/ (super beginner tool)
- KiCAD: http://www.kicad-pcb.org/
- Eagle: http://www.cadsoftusa.com
Are the most popular entry level ones. You can make an ARM or i7 board with either. I think Bunnie is using Altium which is much more pricey.