surprised this wasn't mentioned:
ysmv - your saga may vary - implying that a rules/world interpretation or judgement from SG or Troupe is possible or even expected
thanks. added.
S&M bonuses = Shape & Material bonuses
Also minor nitpick: It should be GotF. 
added
Here's one: WoMS = Wind of Mundane Silence
added
Have you got FitH?
F****d in the Head is not strictly speaking an Ars Magica term
and may violate the Terms of Use if used intemperately.
I haven't seen people using it on this forum.
As it could be taken as a personal attack , that is not very surprising.
I did think your Phoenix Story , while good , was FitH due to lack of player resources for example.
What are the abbreviations for the last few supplements?
C&C is Cradle and Crescent - how far back do you want to go?
Are you sure it's C&C and not tC&tC?
How could I possibly be? These thing are defined only by consensus 
I just tried to pre-empt consensus and make a declaration, and find tC&tC aestethically displeasing and cumbersome to boot.
Well, I'm trying to be descriptive rather than prescriptive.
I found TC&TC once, used by Gremlin44. But as a German proverb says "One swallow makes no summer".
What about those?
The Sundered Eagle:
The Theban Tribunal
TSE
Rival Magic
RM???
The Church
TC??
Legends of Hermes
LoH
The Cradle &
The Crescent
Hermetic Projects
HP????
Apprentices
A?
Grogs
G?
If no abbreviation for a book has been used yet, there is no point in adding it to a list of abbreviations used on this forum.
I've seen RM used in several places. I think most recently and notably in the Ranulf thread. Took me a while to suss it out. Maybe a general note, books may be referred to by abbreviations of their titles. Some may not include articles for brevity.
TSE for sure. Been used around repeatedly already. Same with RM and LoH.
I would go for C&C, even if it might mix somewhat with C&G. Maybe TC&C? Not used much around to deserve an entry, maybe?
Same with the church and hermetic projexts: no abbreviation used around, so does not deserve an entry. Yet.
to be honest, I'll probably end up usng 'Church' for this one I think
I think you've got it right:
TSE: The Sundered Eagle
RM: Rival Magic
TC: The Church (although I wouldn't use it)
LoH: Legends of Hermes
Ok, I'll add them. Thanks.
Respectfully I'd point out the existence of "Cause and Cure", which has already claimed C&C.