I rarely talk up commercial products, but a piece of open source software doesn't count, does it?
I'm talking about the new release of OpenOffice.org -- both the address of the webpage and the name of the software -- which I use at home and which we use at the church to produce the newsletter and order of worship. There are five things I like about it:
(1) It is free; (2) it is easy to use; (3) in its 1.1 release, you can export to PDF, thus saving you a minimum of $65 in other software costs; (4) it makes folded-leaf booklets (including an order of worship) with all the pages in order; and (5) did I mention it was free.
I first learned about it -- back when it was StarOffice, which is going commercial -- from Labarum, a British military chaplaincy site that has ready-to-print service booklets.
But going from the 1.0 release to 1.1, it has ballooned in size, so unless you have a very fast connection, do as I do and find a DC-ROM distributor, and get the software mailed to you for a nominal fee. (I paid $5.95 from a vendor on Ebay, and was quite pleased. And you can share the CD-ROM.)