A Hermes obsession takes a lot of work. The prestige and appeal that comes with owning one of their timeless bags is not easily acquired. The most famous Hermes handbag, the Kelly Bag, is among those most coveted by "bag snobs". Coming in at a close second is the Birkin, one of the most popular of all Hermes purses. These two bags are in hot demand by celebrities far and wide.

Dozens of show business personalities are often seen sporting Hermes handbags in airports, on the streets of New York, and on the West Coast. Some of the most notable figures include:

• Kelly Osborne: The queen of darkness, Kelly was spotted working a crocodile Birkin with her signature look of black on black. The bag was accented by a black dress, a cocky hat, and Kelly’s "black as night" lined eyes.

• Katie Holmes & Suri: Spotted on Madison Avenue of New York, little Suri had her own pint-sized version of Mom’s orange Hermes shopping bag. Later on, Katie was seen with a rare burgundy Garden Party Handbag that looked more like a boarding bag. The Hermes handbag offset her black pencil skirt and red heels. With all the goodies that could be stuffed into that spacious bag, Holmes was ready for anything.

• Nicole Ritchie: Rocking a bag the way only Nicole can, the star ducked under the radar with her orange Birkin at a defensive driving course. She paired the classic bag with up black leggings and boots.

• Britney Spears: The young mother was seen sporting a classic Kelly Bag, complete with her little doggy! On a shopping trip, the singer paired her black crocodile bag with a sheer, purple dress. Even after a little fender bender, all that was noticeable was Spears’ Hermes handbag in the center of the paparazzi’s shots.

• Victoria Beckham: Nobody "bends is like" Vicky when it comes to Hermes purses. Easily voted the most avid collector among celebrities, Beckham is rumored to own close to fifty of the handbags. It seems that the white Birkin is among her favorites; she’s paired it with white capris and a blue and white nautical mini hoodie, as well as jeans, a poet top, and her caramel boots. The former Spice Girl kicked it up a notch when she was noticed carrying a Himalayan Croc Birkin decked out with diamonds. Her classic black dress and broach paled in comparison to the rare Hermes handbag on her arm.

• Grace Kelly: The woman who started the revolution! Then former starlet and new Princess of Monaco was spotted in New York in 1956 carrying a black crocodile Hermes handbag to cover her pregnant tummy. (Inside was the future Princess Caroline, also a future Hermes owner.) The bag was known forever afterward as the "Kelly bag", and is ranked in the top five classic bags by BagSnob.

• Jane Birkin: The woman for whom the Birkin was created, Jane had a chance encounter with Dumas-Hermes on a plane when she dropped her date book. Some time later, Dumas-Hermes designed a bag for her that is now the commonly recognized Birkin bag.

• Carolyn Bessette Kennedy: With John Junior on her arm, and dressed down in a simple but elegant black dress, her Kelly bag almost went unnoticed—but not quite. The graceful woman carried the bag in gloved hands, reminding the world that above all else, she was still a lady.

• Kelly Klein: The former Mrs. Klein seems to have switched teams and is now batting for Hermes. She was seen sporting a powder blue Birkin to complement her casual uniform of jeans (Calvin Kleins?), black riding boots and jacket, and a black turtleneck.

The differences between the Kelly and Birkin bags are not always easily spotted. Similar in size and textiles, their most notable differences are not always detected by the naked eye.

• Each Kelly bag takes an average of 18 hours for production, with the entire construction tackled by a single craftsman.

• The Hermes house turns out 5 Birkins each weekly.

• The Kelly is closed at the top, while the Birkin is open, making it the less formal of the two.

• The Birkin has two handles, while the more formal Kelly has only one.