Re: lump on foot
Since you did post on the cancer board, I suppose I should tell you that my oldest son had cancer and the cancer started in his left foot. It was a rare childhood cancer called rhabdomyosarcoma. There was no obvious lump--both his feet looked the same, but the tumor grew and completely filled the space between the bones about midway of his foot--only 6cm by 2 cm--it had already spread to his bone marrow and even after 4 months of aggressive chemotherapy it came back in bone marrow and took his life on August 25, 2005. If there were any symptoms at all in his foot it was that he had problems with it cramping.
That said and I didn't mean to scare you--your lump is probably nothing, but it would be good to have it checked out considering you are having some pain even without putting weight on it.