A WebmasterWorld thread has nice discussion around what small changes one can make to a site that would have a nice impact on their search rankings.
Often existing sites that did not think about how spiders work can make small quick changes that would have a huge impact on how well that site ranks. But what about existing sites that already have done the daily SEO stuff?
This thread talks about those small, tiny SEO changes that can make an impact. Here are some of the changes people are talking about in the thread:
- Adding keywords to pages within the content and title tag
- Changing the anchor text in the navigation
- Bulking up the text on a page
- De-optimizing a site
- Adding "three semantically related phrases to content area of a problem page (in anchor text)," via Tedster
- Added one phrase to the home page
- Adding longtail keywords back
- Doing Nothing
The last is my favorite, yea - doing nothing and letting Google figure out that you have the best content and most useful site in your niche. Unfortunately it doesn't always work that way.
Forum discussion at WebmasterWorld.

Comments:
Justin C
12/21/2010 04:42 pm
It's amazing how often doing nothing and just patiently waiting works.
David Scoville
12/21/2010 05:05 pm
Interesting that none of these changes are off-page. Without even thinking about linkbuilding, one can really gain some early traction by simple on-page changes. SEO is definitely not as "magical" as some people think.
Amit Verma
12/21/2010 05:05 pm
Its like doing nothing after doing a lot...
Seo Queen
12/23/2010 06:54 pm
This is surprising to know that by only doing on site optimization, someone is getting great results. This it the first time in my 4 years career that I have seen anything like this.
Seo_finder
12/24/2010 03:44 pm
I would add: Check the quality of your competitors on page optimization
Elazar
05/17/2011 07:23 pm
Hi, I know we are in 2011 after Panda. But I shall go and try to implement some of those methods