I'm so in love with the Internetz, I think I'll marry it.
I just semi-borked a load test I was supposed to be tracing…perfmon wouldn't start at the last minute, and in the scramble to get it going, I not only forgot to start my SQL trace, I also left the perfmon output file in BLG format. Honestly, I'd never paid any attention at all to the BLG format. As it turns out, that's the binary output format.
I did a search and came up with this Grant Holliday blog about Relog.exe. Relog is included in Windows, and you can use it from the command line to (among other things) convert a binary perfmon file to CSV.
I. Love. The Internetz.
Here's the command I used to get my readable, Excel-formattable numbers: relog logfile.blg -f csv -o logfile.csv
Happy days,
Jen McCown, http://www.MidnightDBA.com
Edit: Be sure to go read Buck Woody's blogs "Using Perfmon with SQL Server", Part One and Part Two.
Edit 2, 1/19/2010: Just found a couple of great blogs by John Pertell that greatly expand on relog: What I Learned Today – the RELOG utility and Using the RELOG Utility – Part 2