Back to topic:
...You just spent over a hundred dollars, buying massive virtual shelves filled with year old games.

... you walk around town seeing potential marks for GOG stickers.

...you've got more than one star :-D

You feel the need to promote GOG above all other digital retailers, and also promote it shamelessly on all the other forums you visit.
(like on half my Escapist posts!)

...you have built your very own game shelf (in RL) that looks exactly like the virtual shelf 2.0.

...you pray to the Norse Gods every thursday that the GOG Supreme Council of Ultimate Wizardry will release one of the games you've been waiting for.

...GOG releases a game you already own multiple copies of, and you buy it anyway. Also what Vagabond said.

What phanyboy4 said, and:
... You own almost half the catalog of games on GoG (48 here...). And there is apparently people who own the entire thing.

...of the last 15 games you've bought, none of them are new releases.

You send links to free GOG stuff to non-gamers in the hopes you can convert them to the cause of justice, right and decent DRM free gameplay

... You start largely pointless DRM disussions with people you dont actually know.

... You bought 50 games... only to have only played 5 of them.

... you race to post a link to the wishlist after someone starts a topic about a single game which should be added to the catalogue - but realise Cogadh has beat you to it.
... you find yourself explaining what DRM is and why its bad to your parent's dinner guests when they asked what you do for a living - even though the two are completely unrelated. (True story)
... you think post signatures, profile pages and other common forum functionality is clearly overrated - but secretly wish you could at least find your own damn topics easily.
... even thinking about Monkey Island gives you a semi
... you create a totally independent site which feeds the Wishlist data into a cognitive and readable format - just so the games you added to it will get more votes.
... know the this forum is a total sausage-fest but still forget sometimes Aliasalpha is a dood because of his profile picture
... thinking about System Shock 2 gives you a raging hard-on
... you're still waiting for your free stickers to turn up (dammit where are they?)
... you barely struggle to make multiple entries for this list.
Okay I'm stopping now.

haha rommie that shit is CLASSIC

I CONCUR.
Dude should get a star just for that.
The dinner guests/hard-on ones cracked me up especially. :)
As for me:
...you check GOG daily to see if there's a regular/surprise announcement.
...you participate in contests, and win.
...you gift GOGs to your friends and family in hopes of getting them as addicted as you.
...upon gifting game to a friend, friend asks you if the installers can be shared with anyone, and you proceed to give them an extensive lecture on why they should not do this, and beg them to gift the game instead (they do).
...when looking at the price of a new game you think to yourself how many GOGs you could buy with the money instead.
...you don't bother trying to resist the weekend deals anymore.
...you use the GOG demos thread to try everything you're even remotely interested in/find new stuff to add to your collection.
(all true stories)