Note 5 - Stockholders' Equity, Options, and Warrants (Details Textual) - USD ($)	1 Months Ended	6 Months Ended
	Jul. 31, 2018	Jun. 30, 2024	Jun. 30, 2023
Share Price (in dollars per share)		$ 0.03
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		3,075,000
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)		$ 0.04
Series C Preferred Stock [Member]
Preferred Stock, Shares Outstanding (in shares)		4,063
Preferred Stock, Redemption Price Per Share (in dollars per share)		$ 1,000
Preferred Stock, Dividend Rate, Percentage		6.00%
Preferred Stock, Convertible, Conversion Price (in dollars per share)		$ 0.1
Dividends		$ 243,030	$ 243,780
Common Stock Dividends, Shares (in shares)		1,808,400	2,266,500
Dividends, Preferred Stock		$ 90,420	$ 90,660
Dividends, Preferred Stock, Cash		152,610	153,120
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 112,003
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 9 months 18 days
Share-Based Payment Arrangement, Expense		$ 84,400	$ 224,846
Qualified Options [Member] | Share-Based Payment Arrangement, Employee [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		2,050,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)		$ 0.04
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value		$ 57,275
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum		4.56%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum		4.66%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate		0.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum		72.94%
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum		78.11%
Qualified Options [Member] | Share-Based Payment Arrangement, Employee [Member] | Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)		5 years
Qualified Options [Member] | Share-Based Payment Arrangement, Employee [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term (Year)		7 years
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 5 months 15 days
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 107,037
The 2015 Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)		17,217,546
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	20,000,000
Employee Stock Purchase Plan [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)		143,098	191,390
Proceeds from Stock Plans		$ 4,865	$ 4,880
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)		2,081,446