One of the better ones- Samsung 830 series 256gb:

http://img01.static-nextag.com/image/Samsung-MZ-7PC256B-WW/6/000/009/593/880/959388094.gif

Available for $149 on eBay:

http://www.ebay.com/itm/Samsung-830-Series-MZ-7PC256B-WW-256GB-2-5-SATA-III-MLC-Internal-SSD-Single-Unit-/300799070126?forcev4exp=true&forceRpt=true#ht_6552wt_1016

SSDs do not require defragmentation. Say it takes 15 minutes a week to defrag. That is 13 hours in time saved over a year.

(The 830 to be replaced by the 840, which is not yet available)

There are some technical issues with SSD drives when it comes to encryption, which might be of some concern to WNs.

I am not sure but it can be case with a software-based encryption only, so built-in hardware solutions could be fine. Google for more info if interested.