What a great question! There are online newsletters, but as far as traditional paper subsciption-type magazines, I don't know of any but I'd definitely be interested.
There have a lot of articles on hybrids recently.
Motor Trend usually has a blurb of some sort on the topic (this month "oddball" steam hybrids).
Scientific American had a hybrid comparison article last month
http://www.insightcentral.net/forum/vie ... php?t=4613
The May/June issue of
Solar Energy features a Ford Reflex on the front cover (parked in the driveway of a desert house...with goofy fake-looking red flowers poking out of the dirt near the wheels) and this cover reads "Why the car of tomorrow may be solar-powered"