1) avoid flying inside clouds. It's almost free and the PAX get a much better view as well.
2) monitor 130.4 and use it to try to establish if there are gliders inside the cloud you want to fly in. Again it's free.
3) get yourself one of the standalong Flarm units, currently just over £500 for a Swiss Flarm which is stand-alone and can be mounted using Velcro. If you don't have a suitable power outlet in your plane you could use a small rechargeable battery. If I could buy and fit a transponder for that sum I would, and so would most other glider pilots that fly XC.
Well we are just going round in circles.
The answer is simple.
The glider community should write to a company like TRIG and see if a self contained transponder can be developed for around £1,000. If it can they should petition the CAA to allow fitting and to be allocated a dedicated code. Job done.
If such a unit cannot be developed or approved then the glider community is entitled to say we have tried, we have made an effort to properly regulate our sport.
In the mean time I shall be writing to the CAA and EASA pointing out that the practice of gliders operating in cloud is an en route hazard to every other airspace user and they should introduce regulation without delay.