New postal rates are set to take effect Monday, May 14, with the cost of a first-class mail stamp increasing to 41 cents. However, the costs to set loose your snail mail aren't increasing across the board.

The U.S. Postal Service's new pricing plan takes into account not only the weight of the mail, but its size and shape as well. You may be able shave the cost of mailing your care packages and love letters simply by carefully considering your packaging options.

A spokesperson for the USPS says, "If the contents of a first-class 2-ounce large envelope can be folded and placed in a letter-sized envelope, the mailer can reduce the postage by as much as 39 cents per piece. If a first-class 6-ounce parcel can be configured as a large envelope ... mailers will save 33 cents."

The tools and calculators for weighing your options are available at the USPS website.

The new USPS plan also will simplify international mailing options to four: Global Express Guaranteed, Express Mail International, Priority Mail International, and First-Class Mail International.

If you've already stocked up on the USPS's Forever Stamp -- stamps that will cover the cost of a first-class mailing regardless of cost increases in the future -- good for you. Although that won't help this time, as the Forever Stamp already costs 41 cents, you're still prepared for future increases in postal rates -- thinking ahead like a smart investor should.

Here I am in my early 30s, already complaining about how inexpensive things used to be. While my grandparents would tell me about their 10-cent movie dates or $10,000 homes, I recall the 22-cent stamp fairly vividly (apparently, when I was born, my birth announcements could have been sent for a dime a pop). In my memory, I've seen the price of sending first-class correspondence rise from under a quarter to, as of May 14, 41 cents. In fact, rates have been hiked 13 times in 32 years.

But folks wanting to plan ahead can stock up on the "forever first-class stamp," unveiled this morning at the National Postal Forum. The stamp, featuring an image of the Liberty Bell, will go on sale April 12 for 41 cents but will feature the word "forever" instead of a price. The plan is for this stamp to remain valid into perpetuity, even as postal rates inevitably climb. Introducing the new postage, Postmaster General John E. Potter quipped, "Who said nothing lasts forever?"