In their latest IGN blog entry, N creators Metanet listed a bunch of recommended freeware and shareware games. Some of the picks are pointed out as having helped inspire the N game design. The first, Zone Runner, is described as " You run, jump, and collect gold. And die. A lot. Sound familiar?" Other games mentioned specifically as inspiring include Puchiwara no Bouken (which looks like the missing link between Lode Runner and N) and Super Bubble Blob.
Since we claim total ignorance of PC freeware games that are not N or Cave Story, we now have some homework ahead of us! As do you. We normally aren't in the position to link to a bunch of freeware PC games, but this time there's evidence of a direct influence on an upcoming (highly anticipated) DS game.