Hi,
I'm a coder from Slovenia.
I like writing JavaScript and Python. I'm learning Haskell.
Here is my github: http://github.com/Swizec
I have a blog at http://swizec.com
Most recently I did cool thing X <relevant link, this changes every couple of months>
Cheers, ~Swizec
Joining a startup is a two way street. If you are considering joining one, you should do as much diligence (or even more) than they are doing on you. I, personally, love startups -- the energy, the diversity of problems, the ability to learn and grow. But, I've also been bitten by all the glitz (early in my career during bubble one) as well as people that thing "it's a startup" is an excuse to demand above and beyond efforts on a regular basis.
In general, you are going to work more at a startup, you may or may not get paid less, and you will need to weigh the whole work/life balance thing, most likely. You might be asked to make a tradeoff between equity and salary.
The tangibles you have control over (salary, time you are willing to commit, etc) are the ones you need to weigh. But, you also need to understand as much as you can about the expectations of those in management.
Poor planning, for instance, should never be excuse by "this is a startup" -- I don't mean pivoting, I don't mean tweaking as new information comes along, I mean those people that can't make up their mind on what constitutes the expected deliverable by a particular date.
Which startup I'm "with" changes every couple of months.
As for the Google situation, they came to me and I decided to go along with it. To see how far I get and have some external benchmark of my programming prowess. If I do end up getting an offer, I'll then decide whether I want to work with them. Before that I ask every engineer I get to talk with about their working environment to gauge whether Google is the type of company that has retained enough of a startup spirit for me to feel productive there.