They should post their projects. A lot of VCs and investors read HN.
There's already a way for HN readers to post their projects. It's called "submit" and it's in the orange bar at the top.
(Also, that link doesn't seem to list the most recent posts, or at least not at the top of the list. I think there have been more recent review posts than the top few on that list. Some use variations on the searched terms, for example "rate" rather than "review".)