Google had logos for Open Ceremony, archery, diving, fencing, rings, hockey, rafting, tennis, shot put, pole vault, synchronized swimming, hurdles, basketball, slalom canoe, soccer/football, rhythmic gymnastics and today's closing ceremony. The hurdles, basketball, slalom canoe, soccer/football logos were all addictive interactive logos that probably wasted countless hours of employee productivity.
Google Closing Ceremony Logo:

Opening Ceremony:

Archery:

Diving:

Fencing:

Rings:

Hockey:

Table Tennis:

Shot Put:

Pole Vault:

Synchronized Swimming:

Javelin:

Hurdles (interactive):

Basketball (interactive):

Slalom Canoe (interactive):

Soccer (interactive):

Rhythmic Gymnastics:

Google Closing Ceremony Logo:

Google Closing Ceremony Logo:
Opening Ceremony:
Archery:
Diving:
Fencing:
Rings:
Hockey:
Table Tennis:
Shot Put:
Pole Vault:
Synchronized Swimming:
Javelin:
Hurdles (interactive):
Basketball (interactive):
Slalom Canoe (interactive):
Soccer (interactive):
Rhythmic Gymnastics:
Google Closing Ceremony Logo:
Google Olympics Soccer/Football logo
Google Olympics Hurdles Logo
Google Olympics Basketball Logo
Google London Olympics 2012 Slalom Canoe Logo
Google London 2012 Basketball Logo
Source: London 2012 Closing Ceremony With All The Google Olympics Logos