TI websites

Official

General

• Official TI calculator site
• z80 CPU Site

Community

Archives

• ticalc.org
• calcG.org

Forums

• Unitedti.org
• MaxCoderz forum
• Revsoft forum
• DS forums
• Cemetech forum
• Omnimaga Forum

Other Wikis

• TI-Basic Developer
• z80 Heaven

Guides

• technicalc.org
• The Guide

Active Teams

• Revolution Software
• MaxCoderz
• Coders of Tomorrow

Inactive Teams

• Void
• SiCoDe

IRC

• #omnimaga
• #unitedti
• #tcpa
• TCPA

Programmers site (experiments)

• Brandon Wilson site
• Ben Ryves blog
• Michael Vincent
• James Montelongo experiments

French Sites

• ti-fr.com
• ti.bank.free.fr
• ti83.free.fr
• tibank.forumactif.com
• lycos.fr
• tift
• ti-wiki.pbwiki
• yaronet

German Sites

• MobiFiles

Dutch Sites

• there is at least one

Projects

3rd party OS

• LIFOS
• LIFOS blog
• Vera
• PongOS
• OS2
• XOS

Others

• z80 assembly API
• CLAP project
• BELL project
• USB8X
• MSD8X
• USBTools
• DoorsCS

Online Tools

• SourceCoder2 (TI-BASIC editor)