Chemistry Functions including a Moles calculator and equation balancer from Jon Glassman. The site helps you do various calculations related to chemistry.
www.chemfunctions.com

Periodic Table of Data is designed to allow students and teachers to select from a wide range of data from the Periodic Table.
www.rsc.org/education/teachers/learnnet/ptdata/welcome.htm

Humour:
paul.merton.ox.ac.uk/science/administratium.html
New element discovered - administratium

Comic Book Periodic Table [Kentucky, USA]
www.uky.edu/Projects/Chemcomics/
Including "The Answer Man's interactive trivia quiz on chemistry and
comics".

Poetry:
The Periodic Table of Poetry, read a poem about an element or submit your own for unclaimed elements
superdeluxe.com/elemental/

This table combines Japanese Haiku poetry and chemical data for each element www.iscifistory.com/scifaku/elements/periodichaiku.asp