If you were a 3Com (COMS:Nasdaq - news) shareholder on July 27, you might be looking at your Palm Pilot differently these days.

Not only do you own stock in the maker of that ubiquitous electronic organizer, but you might also be contemplating trading in your current model for the new "Palm Vx Claudia Schiffer Edition." More on that later.

3Com completed its spinoff of Palm (PALM:Nasdaq - news) to shareholders on July 27. That's the good news. The bad news is you now have to allocate the cost basis of your original 3Com investment to your new Palm shares.

For the uninitiated, your cost basis is a fancy term for what you paid for a security. When you sell the stock, the difference between the sales price and your cost basis is your taxable gain (or loss). Keeping track of what you have invested in a stock is usually straightforward, but when your company is involved in a merger or spinoff, it gets tricky.

3Com, for example, decided to spin off its Palm division, which makes handheld computing devices like the Palm Pilot, in two steps. In early March, it sold about 6% to the public. Last week, the remaining 94% was distributed to 3Com shareholders. Palm replaced 3Com, in the S&P 500 index that day as well.

So if you were a 3Com shareholder as of 4 p.m. EDT on July 27, you received 1.483 shares of Palm for every share of 3Com you held. (That ratio was calculated by dividing the 532 million Palm shares 3Com was holding by the number of 3Com shares outstanding on the record date, July 11.) The new Palm stock will be distributed in about a week.

The cost basis will be the opening price of 3Com ($13.375) and of 1.483 shares of Palm ($33.875 x 1.483, or $50.24) on July 28, the day following the Palm distribution.

Those prices and some number-crunching add up to show that 78.98% of your original 3Com cost basis goes to the new Palm shares, the company figures. The remaining 21.02% of the original cost basis stays with the 3Com stock.

Bring on the example.

Let's assume you bought 1,000 shares of 3Com a year ago for $24 each. Your cost basis of each 3Com share then is $24, or $24,000 in total. (If 3Com paid dividends -- which it doesn't -- and you reinvested them, you would have to work that into your cost-basis calculation, too.)

As a shareholder on July 27, you qualified for 1.483 shares of Palm for each of your 1,000 3Com shares. You now have 1,483 Palm shares.

You must allocate 78.98% of what you originally paid for 3Com to your new Palm shares. So, $18.96 ($24 x 78.98%) will go to each 1.483 shares of Palm. But you can't stop there. You need to know the basis of a single share. So divide $18.96 by 1.483. Each share of Palm then has a basis of $12.78. With Palm trading around $39 on Aug. 2, that should make you happy.

Now allocate the remaining 21.02% of your original cost basis to your 3Com stock. Each 3Com share now has a basis of $5.04 ($24 x 21.02%). These shares closed Wednesday at around $14.

Stockholders will get an updated information statement addressing this cost-basis calculation in the mail with the upcoming annual report, according to the company. In the interim, check out the 3Com Web site for more info.

The Claudia Schiffer Edition?

In an effort to bring handheld devices to folks other than the gadget-geeks, Palm has brought in a supermodel.

The "Palm Vx Claudia Schiffer Edition" seems to look just like a regular ol' Palm V except for its fancy new blue brushed-metal case instead of the regular silver color. You can only order this must-have from Claudia's very own Web site at www.claudiaschiffer.com. (Down, boys. The site isn't up and running yet.)

But here's a challenge for you: Aside from Claudia's mom, find me a woman who's going to purchase this thing?