Monoprice ([url=http://www.monoprice.com/Search/Index?keyword=zwave]Search -ZWAVE[/URL] - HDMI Cable, Home Theater Accessories, HDMI Products, Cables, Adapters, Video/Audio Switch, Networking, USB, Firewire, Printer Toner, and more!) has their door/window sensor ($24.88) and motion sensor ($24.18) on sale. Use code 5FEB for $5 of a $25 order.
Monoprice does charge shipping. Adding 1 sensor to my 2 sensor order, upped shipping from $3.40 to $9. So I placed 2 orders of 2 sensors each. One via my MP account and 1 via Amazon Payments. Both were e$3.40 shipping each and $5 (5FEB code) each taken off.
Prices on the site seem to fluctuate. If they are not like the above, check back a little later.
I already have 3 of the PIR ones and like them. Got 2 door ones so I could put one on my garage back door and one on my mailbox. Also needed a PIR for the garage and considering putting one in my lanai