Don't have a favourite SP (don't have SP at all). As for the costume, how about:
(no order)
1.Japanese schoolgirl uniform
2.SS uniform
3.Businesswoman
4.Secretary
5.US paratrooper unifrom
6.S&M style (lady's choice)
7.No clothes, but a NSDAP armband
8.No clothes, but army boots
9.No clothes, but a cowgirl hat (that one I stole from V. Veronica's brief explanation of asian cowgirl...holy crap

)
10. Dress exactly like Brtiney Spears in movie clip "Oops, I did it again" (I don't know why, but I hate that b&&c)