Links for mathematics: (see also here )
Math. Departments Servers List (Very useful!)
Karte von WWW-Servern mathematischer Fachbereiche und Fakultäten (Germany only, of course)
Classification Systems (Karlsruhe) (Searchable index)
Mathematics Calendar (maintained by AMS)
Mathematisches Forschungsinstitut Oberwolfach / Mathematical Sciences Research Institute
Newton Institute Home Page / Institut Mittag-Leffler
Sloane's On-Line Encyclopedia of Integer Sequences (You name it, Mr Sloane probably got it!)
History of Mathematics (Lots of biographies including pictures and references)
GAP - Groups,
Algorithms and Programming.
FDLIST-
Information list for representation theory of finite dimensional
algebras
Broué's abelian defect group conjecture (Page maintained by J. Rickard)
Dade's conjectures (Page maintained by K. Uno & J.B. Olsson)
Dave Benson's Home Page (Includes an impressive preprint archive on Groups, Representations and Cohomology )
Kate Fenchel / Richard Brauer (Persons who have influenced me)
Allgemeines zur Mathematik (D. Bargman, Kiel)
John Conway's
Game of Life (in Java)
Mathematical
Fiction
Homepage (Compiled by Alex Kasman) )
Formens evige Magie (by Hans Christian Andersen)
I understand equations, both the simple and quadratical,
About binomial theorem I'm teeming with a lot o' news,
With many cheerful facts about the square of the hypotenuse." (W.S. Gilbert)