BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 14,104	$ 8,061
Short-term investments available-for-sale	4,205	23,615
Accounts receivables	1,965	54
Unbilled receivables	1,836
Prepaid expenses	2,441	1,342
Other current assets	1,558	265
Total current assets	26,109	33,337
Property and equipment, net	6,857	8,206
Goodwill	33,141	33,141
Other non-current assets	469	160
Total assets	66,576	74,844
Current liabilities:
Accounts payable	2,645	3,572
Accrued expenses and other current liabilities	4,528	6,273
Current portion of notes payable	20	80
Deferred rent	386	341
Total current liabilities	7,579	10,266
Warrant liability	368	2,842
Deferred revenue	2,500
Non-current portion of notes payable	300	320
Deferred rent	1,980	2,366
Total liabilities	12,727	15,794
Commitments and contingences
Stockholders' equity:
Preferred stock, $0.01 par value, 2,000,000 shares authorized; no shares issued and outstanding
Common stock, $0.01 par value, 200,000,000 shares authorized; and 117,480,867 shares issued and 117,025,437 shares outstanding at December 31, 2011 and 111,492,014 shares issued and 111,036,584 shares outstanding at December 31, 2010	1,175	1,115
Additional paid-in capital	383,948	371,477
Notes receivable from former directors		(1,572)
Accumulated deficit	(329,656)	(310,292)
Treasury stock, 455,430 shares, cost basis	(2,450)	(2,450)
Accumulated other comprehensive income	832	772
Total stockholders' equity	53,849	59,050
Total liabilities and stockholders' equity	$ 66,576	$ 74,844