Is there any way I can file online even though I was unemployed and earned zero income?

[bluedeb]

If you have no income of any kind (W-2, Social Security, Disability, etc), there would be nothing to put into a return.  You cannot file a blank return.

[DoninGA]

If there is no income to enter on a tax return, then there is no need or reason to file a tax return.  The IRS will not process a tax return with no income entered.

There will be more information coming in the next few days for these type of situations for the stimulus funds.