Update: Book's Purchased!
(1) Surprise, surprise - it turns out that I have a hard time resisting Calvin. The deal on the 7-volume tracts and letters set that Nathan pointed out was simply too good to pass up, so I marshaled some other resources and placed my order. I'm just hoping that when the volumes arrive I will not discover that I already have large portions of these texts in other editions... But that's what return labels are for.
(2) I've been wanting to read this book for some time, and it is an even better price-per-page deal than that Calvin set. Bellah is always interesting, insightful, and provocative.
(3) One friend suggested (outside the official comments thread) that I buy some more Bonhoeffer, and this was a very attractive proposal. But that would have eaten through my whole gift card allowance and that was not attractive. So I decided to go with Robert Jenson, which is never a bad idea. Since I'm a professor of religion now, teaching not only Christian theology but all the world's religions, the category of "religion" has become rather important for me and I've been thinking through (with people like Bonhoeffer and Barth) what to make of religion. We'll see what Jens has to add.