I also have an Excel Spreadsheet that I tailored to my needs (since I trained both FAA and JAA and they have slightly different logging requirements/standards). However I also maintain paper logbooks.
The good things about Excel is that with a little knowing of the formulaes it's a quite potent tool for creating various summaries (by class, type, reg, jurisdiciton, timeframe etc etc), not to mention that the layout can easily be tailored to your exact needs.
But again -- I also maintain paper logbooks, and the two I have finished are in a safe deposit box in the bank
