Here are some suggestions pulled (and edited) from a discussion thread in January:

• A kazoo band playing the theme from Hogan's Heros.
• People of all colors dressed in little Aryan costumes (lederhosen for boys, pigtails and Bavarian dresses for girls -- think St. Pauli Girl). The more absurd looking the better.
• A "moon the Nazis" brigade.
• Belly dancers.
• A Nazi mime troup.
• A goose stepping contest.
• A bumbling Nazi brigade that keep bumping into each other.
• Fundraiser for the local foodbank depending on the number of times the Nazis shout "Sieg Heil!" and "White Power!"
• Contest for the best Nazi cross-dresser.
• Local chapter of gay Nazis for discipline.
• Nonsense slogans to echo "Sieg Heil!" such as "Don't smile!" "Nail file!" and "Big pile!"

The opportunities for street theater are truly endless, and I know that we can come up with more good stuff. Use the comments for further ideas or elaborations. See you Sunday!