Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net loss	$ (3,654)	$ (9,803)
Adjustments to reconcile net loss to net cash used in operations:
Depreciation	239	613
Amortization of intangible assets	40	46
Gain on disposal of property and equipment	(2)	0
Non-cash stock-based compensation expense	385	373
Inventory write-downs	0	1,094
Non-cash deferred rent	0	(44)
Change in:
Accounts receivable, net	(391)	74
Costs and estimated earnings in excess of billings on uncompleted contracts	0	7
Inventory	280	2,041
Other current assets	509	(140)
Other assets	4	0
Accounts payable	(754)	(792)
Accrued liabilities	(506)	(106)
Deferred revenue	(246)	0
Billings in excess of costs and estimated earnings on uncompleted contracts	594	446
Net cash used in operating activities	(3,502)	(6,191)
Cash flows from investing activities
Decrease in restricted cash	1	350
Proceeds on sale of property and equipment	2	0
Purchases of property and equipment	(4)	(393)
Net cash used in investing activities	(1)	(43)
Cash flows from financing activities
Principal payments under capital leases and long-term debt	(37)	(33)
Net cash used in financing activities	(37)	(33)
Net decrease in cash and cash equivalents	(3,540)	(6,267)
Cash and cash equivalents, at beginning of period	6,850	13,075
Cash and cash equivalents, at end of period	3,310	6,808
Supplemental disclosure of cash flow information
Cash paid for interest	5	9
Supplemental schedule of non-cash investing and financing activities
Other non-cash additions to property and equipment	$ 33	$ 86