Welcome to "rabb1t's systems page". This page is dedicated to those who would like a full system recommendation. The date listed next to the system name is when the system was first designed. I will change the builds about every 2 to 3 months depending on price and part changes. Build names are chosen in order to help people ponder a specific parts list over several months time.
A note on my recommendations: 
The systems have references to "rank". Each rank is a bracket in terms of power and performance. As you increase rank you will increase your power as well as allowing for higher settings and higher resolutions, increasing your enjoyment of your games.
Rank 1 builds will be what I'd recommend as a minimum for gaming. A rank 1 build will be the lowest cost while not sacrificing too much in performance. For those in an area of the world where (newer) tech is more expensive this will likely be the build you want to look at the most.
Rank 2 is what I'd recommend as the best choice for mainstream gaming.
Rank 3 is a higher mainstream gaming system.
Rank 4 is a high-end gaming system that reaches a bit into overkill, sometimes featuring multiple graphic cards and possibly some bleeding edge technologies. This will offer the absolute best gaming experience and is an ideal choice for the gamer who wants it all without going into total overkill.
Rank 5 is an extreme system with a focus on gaming as well as general entertainment or content creation. It may feature multiple graphic cards or other bleeding edge technologies. This will offer the best gaming experience as well as going beyond into other entertainment.
As you can see, systems become more powerful and more expensive as you increase rank. Note that these systems are all gaming systems, and as such, parts selection is based on gaming performance. Items that frequently have rebates will show their common post-rebate price in green. Also note that these prices do not include any tax or shipping fees that may apply. You may wish to highlight and print the build you are doing for future reference. Global prices may not include rebates and may vary from prices in the U.S. Options for graphics have been included in some ranks to reflect price point scaling differences in the global market. Note that these options may be lower in price, but will also be lower in power. A single more powerful card (compared to dual lower cards) is always the better option.