BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 3,276	$ 4,124
Investments	30	30
Trade accounts receivable, less allowance for doubtful accounts of $6 on December 31, 2013 and 2012	52	1,031
Other receivables	1	27
Inventories, net	976	1,139
Prepaid expenses and other current assets	202	241
Total current assets	4,537	6,592
Equipment and leasehold improvements, net	2,464	3,028
Other assets, net	27	30
Total assets	7,028	9,650
Current liabilities:
Current portion of capital lease obligations	31	35
Accounts payable	503	680
Accrued expenses	323	485
Total current liabilities	857	1,200
Long-term portion of capital lease obligations	10	63
Long-term deferred rent	633	636
Asset retirement obligations	160	154
Total long-term liabilities	803	853
Contingent liabilities
Stockholders' equity:
Preferred stock, $.01 par value, 24,088 shares authorized and no shares issued and outstanding
Common stock, $.01 par value, 35,000,000 shares authorized; 28,481,496 and 28,458,162 shares issued and outstanding on December 31, 2013 and December 31, 2012 , respectively	285	285
Additional paid-in capital	95,761	95,512
Accumulated deficit	(90,678)	(88,200)
Total stockholders' equity	5,368	7,597
Total liabilities and stockholders' equity	$ 7,028	$ 9,650