TMZ:  Charlie Sheen Paid Lindsay Lohan $100K to Cover Tax Debt:

Don't ever say Charlie Sheen's not the charitable type — because he recently cut Lindsay Lohan a $100,000 check to cover the actress' six-figure tax bill. … [S]he and Charlie became close pals while on the set of "Scary Movie 5" back in September. …

During their bonding period, we're told Lindsay and Charlie talked about everything — and at one point, Lindsay mentioned her ongoing tax problems. We're told Charlie offered to cut her a check then and there to get the IRS off her tail, but Lindsay refused. Fast forward to last week — sources close to Lindsay tell TMZ, Lindsay's biz manager received a check from Charlie for $100,000. We're told Lindsay was blown away by Charlie's generosity — and immediately applied the money to her outstanding tax bill. TMZ broke the story … Lindsay allegedly owed Uncle Sam $233,904 in unpaid taxes for 2009 and 2010 — but thanks to Charlie, that number's nearly been cut in half.  

Sheen presumabky will be filing a gift tax return to report the transaction. (Hat Tip: Ann Murphy.)

Update: Forbes, Sorry Charlie: Sheen's $100K Taxes For Lindsay Lohan Itself Is Taxable, by Robert W. Wood