Messenger sounds
Skype
This contains all Skype version 8 sounds, some old sounds still on the server, and even some unused sounds.
All of these were found at https://secure.skypeassets.com/wcss/8-65-0-76/media/(name of file goes here).m4a
This contains all Skype version 7.(insert specific version) sounds and some old left over sounds, basically every .wav file inside of the old Skype 7 EXE.
Discord
Click here to download all the sounds Paint the Human was able to find in Discord as of 10/7/2020
Big thanks to paint the human!#0090 for finding all these files. This one also includes unused sounds, I recommend you download this one over the others.
Thanks to paint the human for telling me what I missed. Includes 4 new files. ARROW_RIGHT, ARROW_LEFT, ARROW_DOWN, and ARROW_UP.
Click here to download all the sounds I was able to find in Discord as of 10/6/2020
Found all of these using inspect element. I may have missed a few so I will eventually go back to this.
TeamSpeak
This contains all the default and default_male sounds in the newest version of TeamSpeak 3 as of writing this (ver. 5.3.6). I do not have access to TeamSpeak 5's beta yet, nor do I know if any new sounds are present or if any are changed, but I will check if I can manage to get a TS5 code.
Pidgin
This contains all the default Pidgin sounds. I am pretty sure they wont add any more sounds in a long time, or ever. All sounds are located in the Pidgin install folder at "\sounds\purple\".