Took two years to forget that. Also bad are commercial jingles like "I wish I were an Oscar Meyer weiner" or the Big Mac song: "Two all-beef patties, special sauce..." I even got this flamenco chord progression lodged in my brain once. But I have the solution! Just push it out by singing a Bach fugue subject to yourself. I find this one particularly effective:
The continuation is complex enough that it won't stay in your brain too long, but it is distinctive enough to over-ride the earworm.