Last year I described a home-constructed bracket for attaching a PDA over the face of an Anabat SD1 bat detector (Ana...nother thing or two about the SD1, November 28 2008)
Although not as strong as the brackets sold by Titley Electronics, my bracket has the advantage that, if dropped during a survey, the bracket is likely to give way and protect the PDA and its precious data. It also cost roughly a 50th of the price of buying theirs, which is handy in the current economic climate.
Several people have contacted me to ask about the design. It's very simple, virtually "Blue Peter" construction, though without the sticky-backed plastic (I could never put that stuff on without bubbles anyway!)
For anyone who wants to try making one, I have put the details onto a .PDF file, accessible here: http://plecotus.net/Anabat-PDA-bracket.pdf
If you make one please let me know how you get on: mailto:email@example.com
My website: http://www.blogger.com/www.plecotus.co.uk