I agree with everyone about the articles. No other information outlet I'm aware of considers the technical/scientific aspects of gear performance. The tests on CO emissions from stoves is worth the $25 to me. So are the MYOG articles; they have saved me far more money than a paltry $25.
It's more than all that though. Like Juston, I see how BPL fosters and supports the UL community. How much harder would running a successful business like MLD, SMD, GG etc. be without this site? How many of the cottage makers would survive? Would we have super-cool cottage makers like ZPacks, eNlightened, or KookaBay without this community to put the word out?
It's funny, years ago while managing a big outdoor shop in SLC, I was talking about the small but emerging UL gearmaker's trend with Jerry Gollar. We both kinda came to the conclusion that the key for success was a different marketing strategy that didn't use big advertising dollars to get the word out. BPL provides a means for the small companies to directly market to a very targeted audience. It also allows near instance feedback on products, allowing makers to fine-tune their offerings in a way that's unavailable/unwieldy for the mainstream companies.
By becoming a member, IMO you are not only supporting this site, but indirectly supporting the entire UL community. I feel I get more value from my BPL membership than almost anything else I buy.