1) You asked a broad question. Ten minutes on google would answer 90% of your question, and bring us all to the same page. Being angry that this was suggested isn't reasonable.
2) JBOD exist (just a bunch of drives). It functionally spans itself so that multiple physical drives appear as only one logical drive. No redundancy, no performance enhancement. There is no reason that I can currently see to have a JBOD array for a home user.
3) RAID has to rewrite each drive. You cannot just put an extra two drives in, then RAID them. Back-up your data, and be prepared for a clean drive.
4) Sweet jebus you're looking at an expensive setup. This is one of the cheapest 8 SATAII based RAID controllers I could find:
http://www.newegg.com/Product/Product.aspx?Item=N82E16816115026 If you really want that then it's your prerogative.
5) RAID =/= backup. It's been touched on already, but RAID arrays aren't a backup. They might allow a number of drives to fail catastrophically, but cannot address slow degradation. Also, remember that you're building an array of the same type of drives. If they have a design flaw then more than one is likely to fail (in rapid succession).
6) Why in Hades do you want 10? You lose half of the drive space. You get a bit of a performance boost. If you're looking at that kind of investment the solution is clear. Buy an SSD for the primary applications, run a 4 drive RAID 5 array for storage, and bite the bullet on 3TB drives. You wind up with the OS drive and 9TB of storage. A ten drive RAID 10 array only creates an additional 6 TB of data, while costing at least 3 times as much (assuming you find a RAID controller that only costs as much as two drives).
TL
R.
Like the 3930k, if you have to ask about this topic you likely don't need it. RAID 10 in unlikely to be useful given that you want data back-up and not continuous operation reliability. You can increase your storage capacity, while decreasing cost, by using RAID 5.