Disallow: /admin/
Disallow: /discussions/admin/
# These are, er, internal admin pages.

Disallow: /smoking_in_pubs_it_makes_the_beer_taste_funny/
Disallow: /humorous_comments_in_robots.txt/
# Ho ho.

Disallow: /show/
# /show/ are internal Ajax/Aha frames

Disallow: /content/ad_468_unsold.muk
# This'll be an internal ad then

User-agent: Googlebot
Disallow: /search/
# Having search results appear when you search is a little, um, odd.