747d360d_ut_Getting_Penalized_by_Google__Donate_money
Well, you get linked for being defaced. Especially by your readers. This is a win to win situation if there is no real destruction done. The cracker can brag about that and you get linked. Many links if the defacement is spectacular enough and people care for your site. [Donate money] 
Pay a cracker to deface your site
20 Ways to Get Legit Paid Links Without Getting Penalized by Google
Donate money