Another week, another message from Facebook about which of your friends have birthdays this week. You could post a message to their wall. You could purchase a virtual gift for them -- the very essence of a symbolic act.

Or, starting today, you could join with others in their social network to make a small cash gift ($1-10) that just might add up to a tidy bundle for the recipient of your collective largess.

Meet Giftiki, a collaborative gifting engine that attempts to extend commerce into social media in ways that may just alter gift giving as we’ve known it up until now.

“Your social network is a lot bigger than your wallet,” says CEO Justin Stanislaw. "With Giftiki, you can contribute small amounts of money to a friend and it won’t break the bank. But, along with 20 or 30 others in their network, it will add up to a significant gift for the recipient.”

The birthday girl or boy can then redeem the gift with an American Express gift card, or directly with Amazon and other online retailers. (S)he can also choose to apply some (or all) of the gift to “credits,” which can then be used to make gifts to others. What will be created here, as is the case with various social gifting services, is a new marketplace where gift monies circulate around inside communities of friends.

One thing that intrigues me about Giftiki is how it proposes to tap into the emotional component surrounding birthdays and friendship. People, of course, have wildly different expectations (and capabilities) for celebrating birthdays and for giving gifts, but traditionally, most feel compelled to do something.

Given an extended recession and high unemployment, however, many are finding it difficult to buy what formerly would have been thought of as proper gifts for one another, because money is just too tight.

Meanwhile, on Facebook, the concept of what a “friend” is has exploded out to include friends of friends and people who perhaps would be your friend if only you ever had the chance to actually meet one another.

Meanwhile, posting a birthday greeting to someone’s wall is an easy way to send a message that you care, and it’s free. But again, traditionally, for close friends, the custom has been to do more than that.

The concept of virtual gifts, which sprang up in recent years, comes from gaming, and requires the giver to spend real money, while the recipient doesn’t actually receive anything concrete.

Stanislaw says it was the rise of virtual gifts that helped him conceive of Giftiki. “It drove me nuts that people were buying virtual icons, and that their money was wasted and literally thrown away. Not at Giftiki -- it’s actual money here you are giving someone, so they can get something they actually want.”

Although at launch the company has restricted its focus to birthdays, there are many other gifting occasions it can and will be adapted to, like anniversaries and wedding registries.

But, birthdays are the initial sweet spot, with an estimated 82 million birthday-related posts on Facebook every day, according to the company. Users will be able to create the equivalent of a “wish list” to help guide friends as to which gifts they aspire to, while a gift-o-meter will record the total amount of gifts to date.

Stanislaw says the team also envisions charitable giving as another way to use the service down the road.

The company says it is the first startup to partner with Serve, the new AmEx digital payments system, which will extend its reach to mobile devices, and make it generally easier for users to manage their gifting activity in the future.

There are quite a few other startups pushing into this space. Giftiki is backed by Tim Draper with an initial round of $1 million.