I got some BLS axle straps for Christmas. I am using them on my Speedplay pedals.
I know there are some decent options out there for attaching the strap to the bottom of the pedal as well - ranging from just running a bolt through the strap into the pedal to the very nice adapters from
Cruz Components.
But I was toying with some other homemade options. I tried using some medal duct strapping strip to create a loop I could bot to the bottom of the pedal. It worked, but was very ugly. But I also started playing with a rare earth magnet, which is strong enough to hold through the strap to the bottom of the pedal. I think I am going to get a larger magnet and glue it to the strap so that it holds to the bottom of the pedal to help keep it in place.