Note 5 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

	Year Ended December 31, 2017
	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value
Outstanding at beginning of year		3,380,615		$	2.00
Granted		1,720,000			0.71
Exercised		(50,000	)		0.36
Canceled and forfeited		(1,362,936	)		1.77
Outstanding at end of year		3,687,679		$	1.50		7.0	$	—
Exercisable at end of year		1,946,445		$	2.15		4.9	$	—

	Year Ended December 31, 2017
	Number of Shares			Weighted Average Grant-Date Fair Value
Unvested at beginning of year		207,000		$	1.17
Granted		200,000			0.51
Forfeited		(50,000	)		0.51
Vested		(207,000	)		1.17
Unvested at end of year		150,000		$	0.51