Just share in a comment and I'll categorize below. Thanks ahead of time for your contribution!
- Cisco Collaboration Systems Documentation : Full matrix of systems documentation back to UC version 6.1. SRND, configuration notes, system release notes, etc.
- Cisco UC Integration for Microsoft Lync 9.7(4) Administration Guide : Detailed guide for integration of Lync into Cisco UC. Don't attempt without using this guide!
- Cisco IOS Voice Troubleshooting and Monitoring Guide : Very comprehensive list of Cisco troubleshooting guides that covers all aspects of IOS Voice. If you aren't sure where to start - Start Here!
- Voice Translation Rules : If you don't make voice translation rules frequently, the syntax can be impossible to remember. Consider this page one of your best friends.
- Cisco IOS 15.0M Configuration Guides : Extensive list of configuration guides specific to IOS 15.0M broken into many categories, including "Voice and Video", "QoS" and "Security, Services and VPN".
Unified Communications Applications
- Cisco Unified Communications Manager IM & Presence Configuration Guides : Good starting point when doing any configuration for IM & Presence.
Collaboration Management and Licensing
- Cisco Prime Collaboration End User Guides : Versions 9.0 through current (10.x)
- Cisco Emergency Responder DocWiki : Lots and lots of troubleshooting guides to assist with a variety of CER-related issues.
- Cisco MCS-78XX Boot Error Codes : Quick list of common boot errors that can happen when booting 78XX hardware.
- DocWiki - Virtualization for Cisco Unified Communications Manager (CUCM) : This is the motherload starting page for all things related to virtualizing CUCM. Contains VM configuration requirements all versions back to CUCM 8.0(2).
- Recognizing and Categorizing Symptoms of Voice Quality Problems : This is the document you wish every user would read before they report that their voice quality is "bad". Defines a vocabulary that can be used to describe quality problems AND includes sound recordings to demonstrate each variation.
Essential Voice Engineer Tools
- TranslatorX : A troubleshooting tool that allows you to quickly parse through Cisco Unified Communications Manager or Cisco Unified Border Element trace files and search for Q.931, H.225, SCCP (Skinny), MGCP, or SIP messages.[submitted by Nick Barnett]
- Notepad++ : A free source code editor and Notepad replacement that supports several languages.[submitted by Nick Barnett]
- Agent Ransack : A free software program for finding files on your PC or network drives.[submitted by Nick Barnett]
- WinMerge : An Open Source differencing and merging tool for Windows. WinMerge can compare both folders and files, presenting differences in a visual text format that is easy to understand and handle.[submitted by Nick Barnett]
- Wireshark : The world's foremost network protocol analyzer. It lets you see what's happening on your network at a microscopic level. It is the de facto (and often de jure) standard across many industries and educational institutions. [submitted by Nick Barnett]