Note 4 - Share-based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Notes Tables

Share-based Compensation, Stock Options, Activity [Table Text Block]

									Weighted
Balance, June 30, 2016:									Average
	Options		Shares			Exercise			Price per
	Outstanding		Available			Price per share			share
Balances as of December 31, 2015		10,241,086		1,758,914		$0.23	–	1.89	$	0.44
Granted		40,000		(40,000	)		0.45			0.45
Expired		—		—			—			—
Balance, June 30, 2016		10,281,086		1,718,914		$0.23	–	1.89	$	0.44

									Weighted
									Average
Balance, June 30, 2017:	Options		Shares			Exercise			Price per
	Outstanding		Available			Price per share			share
Balances as of December 31, 2016		9,916,586		1,981,414		$0.23	–	1.89	$	0.44
Granted		340,000		(340,000	)	0.39	–	0.69		0.65
Exercised		—		—			—			—
Balance, June 30, 2017		10,256,586		1,641,414		$0.23	–	1.89	$	0.44

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2016						2017
	Non Plan			2007 Plan			Non Plan			2007 Plan
Risk free interest rate	1.77	–	1.91%	1.26	–	1.36%	2.29	–	2.40%	2.31	–	2.40%
Expected volatility	641	–	645%	311	–	315%	578	–	601%	578	–	601%
Expected dividend yield		—			—			—			—
Forfeiture rate		—			—			—			—
Expected life in years		7			5			7			7

Outside of 2007 Plan [Member]

Notes Tables

Share-based Compensation, Stock Options, Activity [Table Text Block]

							Weighted
Balance, June 30, 2016:							Average
	Options			Exercise			Price per
	Outstanding			Price per share			share
Balance, December 31, 2015		19,394,975		$0.18	–	1.00	$	0.40
Granted		484,077		0.33	–	0.45		0.38
Exercised		(60,000	)		0.25			0.25
Balance, June 30, 2016		19,819,052		$0.18	–	1.00	$	0.41

							Weighted
							Average
Balance, June 30, 2017:	Options			Exercise			Price per
	Outstanding			Price per share			share
Balance, December 31, 2016		20,148,766		$0.18	–	1.00	$	0.43
Granted		4,552,201		0.43	–	0.67	$	0.47
Expired		(3,866,629	)		0.18			0.18
Exercised		(3,866,630	)		0.18			0.18
Balance, June 30, 2017		16,967,708		$0.18	–	1.00	$	0.41