Programs that I frequently used in my work:

• Statistical environments: R, SPSS and SAS
  
• Structural equation models: EQS, LISREL, Mplus, Mx and OpenMx
  
• Multilevel models: HLM, SPSS Linear Mixed Models, SAS PROC MIXED, nlme and lme4 in R
• Meta-analysis: meta and metafor in R
• Operating system: Linux (Fedora)
• Unix-like environment in Windows: Cygwin
• Synchronizing files among computers: rsync
• Remote desktop control program: TigerVNC
• Programming languages: C and Perl
• Office suite: OpenOffice
• Editor: Vim (and Vim R Plugin) and  Emacs (and ESS)
  
• Search system for Linux: MetaTracker
• Browser: Firefox
• E-mail client: Thunderbird
• Instant messenger for ICQ, MSN, Google Talk and Facebook Chat: Pidgin

Mailing lists that I read daily:

• R: R-help
• Structural equation modeling: SEMNET
• Multilevel modeling: Multilevel modeling discussion list