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Fergie, oh, Fergie: You're such a tease!

The Grammy-winning singer, who's already quite the gung-ho tweeter, beefed-up her social-media cred by joining Instagram earlier this week.

You doing some whoop-whoops? It gets even better.

Fergie flaunts airport fashion, travels in skin-tight red pants

For her inaugural pic, Fergie teased what she plans to wear this Halloween, and we gotta say: It bears an eerie resemblance to a certain trouble-prone celeb.

"What ever am I going 2 b 4 #Halloween this year? #costume," she wrote, attaching a pic of her in a long blond wig with wispy bangs that might make even Lindsay Lohan blink twice and go into a screaming fit with her mom. (Oh, wait: She already did that.)

So whom do you think Fergie's trying to be? Chime in below!

Check out Fergie's other (non-Halloween) fashion statements