Interesting.
I wrote and use my own logbook in Excel. Unsurprisingly perhaps, it's extremely similar to the one at that link - as presumably he and I were both trying to solve basically the same problems with the same tool.
I don't plan to stop using my paper logbook and it's a moot point which is backing which up, but I find Excel an excellent tool for the task.
You're welcome to a copy of mine to play with it you want to drop me a PM with your email address, but I'm sure that one is as good as mine, and with either, as it's in Excel you can just muck about with it to tailor it to your own exact requirements.
The biggest problem with Excel, and its a pretty trivial one, is that it doesn't handle minutes well in calculations. Entering time and date is fine - but what I do in mine is then work in 3 places past the decimal in all the calculations (so 1.5 = an hour and a half for example), then wrote a simple algorithm to turn that into hours and minutes in two columns wherever I need totals outputs to that level of accuracy.
I don't know what the other version does, but I found it worked best to run across three sheets - one for the tabulated logbook, a second for the calculations, and a third which is the summary page for display and printing if anybody wants a logbook summary.
G