I've been scoping out some of my competition and I noticed the number 1 ranking site is doing a lot of "interesting" stuff.  I saw a bunch of 1px blank images that they must be using for the alt tag keywords.  I also noticed several links to internal pages with different keywords without anchor text so they don't actually appear on the page.  Is this considered black hat?  Should I be doing something similar?  It feels like the work I'm doing to try to rank #1 with a clean/professional looking site are wasted when the #1 sites are doing things like this.