Forum Moderators: open
Some ways to make them less similar and more unique:
1) Add specific unique copy text for each product
2) Use different titles and H1 - H2 tags
3) Use different metatags
4) Use different alt tags on images
5) Use a bit of bold and/or italic on the discriminating words.
Try to use the different term "red" vs. "blue" more often in these important places than you use the common term, eg. "widgets"
Of course you would want to link from the red to the blue or green from a conversion and usability wiewpoint. Try to make those internal same-level-page-to-page links so that they do not have the common term in them, unly the difference, eg:
not: <a>Red widgets</a>
but: <a>Also available in Red</a>
Of course you will also want anchor text with the full qualifying name - use that on other pages, eg. higher hierarchy level pages (product category front pages, site maps, etc).
Hope this helps.
/claus