Optical
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AstrOmatic (SExtractor, SCAMP, SWarp, etc.)
K-correction
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Radio
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AIPS
  A small guide to AIPS
  Samuel George's AIPS note for GMRT

CASA
  CASA Wiki
  CASA Hints, Tips, and Tricks
  CASA Scripts and Data
  EVLA Tutorials
  12th Synthesis imaging workshop

MIRIAD (including WIP , 'setmir' on my machine)

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Radio survey
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TGSS (GMRT 150 MHz)
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X-rays
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XMM background and soft
 

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UDS/SpUDS
----------------------------------------------------------
C. Simpson's page on SXDS
SXDS homepage
----------------------------------------------------------

Statistics
----------------------------------------------------------
R:
  R Tutorial
  Learning R
  R-FITS

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Computer language & Linux
----------------------------------------------------------
Python
  Jeremy's Python 123
  NumPy
F90 course 1

GNU Scientific Library (C, can call it from Fortran with a C wrapper function)

NR book on-line

Some linux notes
Astrophysics Source Code Library
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IDL
----------------------------------------------------------
IDL tutorial
Buie's IDL library
IDL Astronomy User's Library
IDL Programming Tips
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Blogs
--------------------------------------------------------------
Cosmic Variance
Not Even Wrong
Plus (online Maths magazine)
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