I maintain a customer service wiki of more than 500 companies, where you can share the phone numbers, email addresses and names of executives who will help you get the service you deserve. The site can be found at On Your Side.

Here are are shortcuts to the most requested categories:

Airline
Appliances
Cable
Car Manufacturer
Car Rental
Cellular
Computers
Electronics
Cruise Line
Email
Hotel
Retail Stores
Restaurants
Telephone/Telecommunications
Travel Insurance
Travel Agency

Note: I’m in the process of upgrading this site to a real wiki running on the Wikimedia platform. If you would like to help with this noncommercial project, please send me an email.