APRS is free. http://www.ew.usna.edu/~bruninga/aprs.html

And it works with both IFR & VFR flights. Of course you have to have a HAM
license and some minor amount of equipment.

As long as we're getting into hardware solutions...
http://skyhelp.net/dmr-200.htm

Not sure that qualifies per the 'cheap' part requested above.
Unit $750
Activation --$50
Monthly subscription --$25 (includes 30 reports), web-mapping extra ($10)

You're looking at $1200+ for the first year and then $400+ per year after
that. With APRS, you'll have a $300-400 up front cost with no charges
after that. But as I wrote, you have to have a HAM license too.
--
Ken Reed
http://www.dentalzzz.com