I play around with a lot of stuff, including

   Malware Analysis
     Malware Binaries (Windows, OSX, Linux, etc.)
     Mobile Malware (IOS, Android, Symbian, etc.)
   Reverse Engineering
     Software/Code analysis
     Software Modification
     Decompilation
     Data Extraction
     Source Code Recovery
     Bindiffing
   Computer Forensics
     Digital Forensics
     Incident Response
     Incident Preparedness
   Data Recovery
     Photos, documents
     Password recovery
   Security Assessments
     Penetration testing
     Security Audits
     Source Code Reviews
   Graphics Design
   Software Development
   Localization
   Others
     Cryptanalysis
     Technical Reviews
     Internet Research (OSINT, etc.)