Open Source Apps for a Law Office?

Pandora's Vox asks: "There seems to be lots of FOSS accounting software out there, including one that is almost exactly what I'm looking for. My father just left a large law firm to set up his own shop, and has been having all sorts of adventures with one of the leading legal billing software packages. It's expensive, inflexible, and monolithic. App by app I'm moving him to open source, which brings me to the question (finally!): is there anything comparable out there in FOSS-land? And if not, a) what's the closest thing, and b) would there be any interest in creating / adapting something for the kinds of time-tracking needs that lawyers have? We're talking minute-by-minute time billing, mostly. With some basic accounting tossed in. I'm hoping to do the lawyer thing in a few years myself, so I figure I should start getting the tools I'll be needing together now. Planning ahead, and all. Thanks a bunch!"