I was trying to find the Office 2013 Keys and all I found was the Windows ones. So here are the links to the key pages at Microsoft.

The keys I use the most at the moment

Software  KMS Client Setup Key
2012 R2 Datacenter W3GGN-FT8W3-Y4M27-J84CP-Q3VJ9
2012 R2 Standard  D2N9P-3P6X9-2R39C-7RTCD-MDVJX
2012 R2 Standard AVMA DBGBW-NPF86-BJVTX-K3WKJ-MTB6V
Windows 10 Professional W269N-WFGWX-YVC9B-4J6C9-T83GX
Windows 10 Enterprise NPPR9-FWDCX-D2C8J-H872K-2YT43
Windows 10 Enterprise 2015 LTSB WNMTR-4C88C-JK8YV-HQ7T2-76DF9
Windows 8.1 Enterprise MHF9N-XY6XB-WVXMC-BTDCT-MKKG7

Links

Acronym Full name
AVMA Automatic Virtual Machine Activation
VLK Volume License Key
GVLK Generic Volume License Key
MAK Multiple Activation Key
KMS Key Management Services