If let's say I were to buy a computer today (I'm not by the way just a hypothetical question) what specs would it need to literally run anything out there. It seems to me some people are going way over board with there systems, but I could be wrong. 

Also how future proof would that machine be, how long will it last?

depends very much as example if you want to play only with 1366xwhatever, 1080p or if you want to play higher than 1080p. and also how many fps are enough for you.

i saw some benchmarks with gtx 680 and 690 and differences between both weren't very huge up to 1080p but with 1600p there was a big difference.

€dit: ok now i saw some other benchmarks on another site and there  is already a big difference in fps with 1080p between gtx 680 and 690. now i have no clue what's correct^^  but one is for sure above 1080p you definately have a huge advantage with the 690.

Two 3.06GHz 6-Core Intel Xeon (12 cores)
64GB (8x8GB) Ram
512 GB solid state hard drive
ATI Radeon HD 6990

It would last you a very long time.

Are laptops becoming decent for gaming yet? I bought an ASUS that was decent for gaming 4 years ago, haven't really looked into newer ones though. One problem is I can hardly get a laptop I use for gaming to last 2 years.

"Run everything out there" is a really open ended criteria.

If you're planning on playing with a WQXGA display or have a 3 way 1920x1080 display set up (why not go nuts with a 3xWQXGA and be the only kid on your block) and you're planning on playing in 3D, the "run everything out there" requirement skyrockets from a basic 1920x1080 single display non-stereoscopic signal.

Reality is, top end VGA card set ups (3x top tier VGA cards) are really only required for those 3 way display set ups and other extra high res output modes.

RAM requirements really haven't changed much; people configure PCs with more memory almost because memory has become so cheap, but even 8GB for gaming covers everything. I'd argue even 4GB covers any current game regardless of hardware overhead, not that anyone should do a new build with so little memory as you'd save next to nothing.

There are a lot of benefits to be milked from the use of SATA3 SSDs, but even with the per GB premium dropping fast, very few will spend the premium to install all their games on SSD. But at minimum, SSD boot drive for OS and most frequently used apps/games.

CPU wise, any of the quad core hyperthreaded Ivy Bridge chips would do. Any self builder is likely to be an overclocker, so K version only. For a new build, there's no need to use older parts.

As for how long it will last, if you spend over $2,000 on a self build, you'd probably be fine for the next 4 years even though you'd lose your e-peen bragging rights within 1-2 years and might not be running those hypothetical 4 year in the future games at max quality/max res at 60+ fps.

It all really boils down to how much you want to spend on an annual basis to keep current.

In most cases, a builder is better off doing a fresh mid/high grade build every 2 years (between $1,000-1,500), recycling the few parts that are salvageable (drives, PSU, case, etc.). Really, all you're replacing is MoBo, CPU, RAM, and VGA cards. Of course that's about 80% of a new PC.

They're certainly usable and a lot more practical for the gamer who is never at home. 

But there's no question laptop gaming is still a compromise regardless of how much you spend on one. 

At minimum you lose multi-monitor set ups since it's impractical and no longer mobile if one were stubborn enough to carry around an extra flat panel display or two specifically for gaming in their giant game laptop suitcase. 

Daily or heavy use laptops in general are a 2-3 year purchase. 

If I was looking to build a system to run everything with my current 1080p monitor at acceptable performance for me. I would probably go for something along the lines of 

i5 3470

8GB RAM

GTX 660 Ti 2GB

Thanks for the reply! Yeah I think I am gonna get a desktop next.

They will not  be outdated in two years.

Just take a look at what was the best available VGA card(s) 2 years ago and you'll see that they are still 3rd and 4th tier cards in the entire hierarchy of VGA cards.

2008's HD4870x2 and GTX295 are still at the top of the 4th tier.

Generally, it's not recommended to bother updating VGA cards unless the new set up is 3 tiers higher or one has enough disposable income to buy minor top of the line updates every year with no regard to price/performance. 

http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107-7.html