What should I do with $100?

I have an envelope with five $20 bills sitting on top of my bedroom dresser. What should I do with this money?

Here's the background. This past summer, I was at a Calvin seminar on writing as Christian proclamation, and we were told that as part of the seminar, each participant would receive an additional $100 for use related to the purposes of the seminar. Originally we considered options like pooling our money together as a lump sum that could be used as a scholarship fund or something that would be used to encourage Christian writers, or to keep the funds as a reserve for us as an incentive - once we reached some goal, like writing an article or publishing a book, we would be sent the money. Ultimately we decided to use the money the way some churches have, inspired by the parable of the talents and the Pay It Forward concept, to use the money in some creative, constructive way for the sake of the kingdom, and then to write about the process and the results. We dubbed our project "Write on the Money."

Then we got word that actually, we don't have funding for this. It turns out that each of us already received our $100 in the form of reimbursement for the books we bought and read for the seminar. But instead of scrapping the idea, our seminar decided to proceed, and we'd come up with the money ourselves. What's been fun so far is that several of us have been surprised with money showing up unexpectedly - one participant received $100 for a medical study she was a part of, and another participant wrote an online article and got a check for, you guessed it, exactly $100.

In my case, this past July I was sent some interview questions about my suburban book by the editor of Youthworker Journal. He was going to put together a dialogue article by interviewing me and another author who had also recently written a book about suburbia. Part of the intent of the Calvin seminar was to set aside time to do our own writing, so one of the things I did during an afternoon was write out answers to the interview questions and send them in. A month or so later, I got a follow-up e-mail from Youthworker Journal asking me to submit an invoice for payment for my article. I hadn't realized that the piece was considered an actual article that I would be paid for. So I submitted the paperwork, and a few weeks ago I got my check for the piece. I deposited the check and immediately withdrew $100 to set it aside for this Calvin project. The envelope has been sitting on my dresser ever since.

So - what should I do with it? Any ideas? One of my fellow participants buried his money in the backyard, to try to understand the experience and thinking of the third servant in the parable of the talents. Since I got the money in conjunction with an article about my suburbs book, I think I should do something suburban-related with it. After all, two chapters of my book are dedicated to issues of consumerism and materialism, and I've reflected a bit on suburbia as a consumer culture. Is there a way that I could use this $100 constructively and Christianly in my suburban context?

I'm open to suggestions! If I end up doing some sort of ongoing project, I'll blog about it periodically here. And if anybody out there has been at churches that have done this kind of project, I'd love to hear what you or others did and what the results were.