Highly recommended

http://www.tascione.com/

www.howstuffworks.com/clock.htm

How Stuff Works

www.clockwatch.de/

Clock Watch

www.materialworlds.com/sims/PendulumClock/install.html

http://www.horology.com

Horology

Timezone

In German:

Clocks and Time

Wooden Clockworks

http://www.nawcc.org/default.htm

National Association of Watch and Clock Collectors

http://www.awi-net.org/

AWI. American Watchmakers-Clockmakers Institute

http://www.bhi.co.uk

BHI, British Horological Institute

http://www.pricelessads.com/

http://www.taylor-time.com/