Is it any good? I'd like to buy a modern city builder, as I don't have any, but I've heard Simcity Societies sucks. I've heard good things about City Life, however. So, any opinions?

Barely average game. You'll be fine with SimCity 3000.

I don't have SimCity 3000, or any "modern times" city builder. If only it was available on GoG...

Global Agenda is 25% off on Steam till 31 May.
Never played it, but I heard that it's a mediocre game.

Try the demo first (if there is one available).
I remember playing a little bit of both, City Life and SimCity Societies. Don't know which one had this, but you had different types of people, some rich, some poor, and if you build something that type doesn't like or use in its neighborhood, all hell would break lose.
I understand that the developers tried to do something different, but seriously, they failed (or maybe I just could not get in, but a lot of other people say the same).
I've wasted days playing SimCity 3000, so I can tell you for sure that it is a better game. Don't really know SimCity 4, but you might wanna check out that too.

Majesty 2 75% off ($7.50) on Steam

Don't trust one which doesn't offer you download service. For example there are many shop selling retail cd keys and you have to download the game from torrent if you want to play.
Btw. you find a lot of info here.

OffGamers is a site that matches your description, but I think that they sell only keys for MMO games.
A friend of mine bought few WoW keys from there, and they all worked correctly.

Sooo...that german give-whatever-you-want store is up...and people have been reporting problems.

Yeah, they had technical problems, but here is a blog entry from the Bob Came in Pieces' developer's site. According to the entry, this new indie bundle site looks totally legit.
But just to be safe I'd still wait for a few days before purchase.

The definition of a workable scam is that it looks totally legit. Based on the previous material I've read, and the apparent postings by the apparent owner himself on the site, I think I trust this less than I would trust my boss if he were to suddenly burst through the door and declare that he is, indeed, Napoleon.

Gamersgate game of the week: Sid Meier's Railroads! 50% off ($4.97)

Thanks, I was thinking of G2play.. I wasn't thinking of buying from one of them, I just wanted to look at them.

about g2play
bought EA game cd keys from them , all worked correctly
bought Blizzard cd keys from them , alll worked correctly
bought The Orange Box cd key from them ( i've got the cd key scan ) worked
bought retail cd key from them (East India Company, East India Company: Pirate Bay ) they were fraud cd keys ( not worked on Impulse ,but the Majesty 2 cd key worked )
If i were you , i wouldn't buy any retail cd keys from them ,only with DD .