-brazil- writes "Every programmer forum gets a steady stream of novice questions about numbers not 'adding up.' Apart from repetitive explanations, SOP is to link to a paper by David Goldberg which, while very thorough, is not very accessible for novices. To alleviate this, I wrote The Floating-Point Guide, as a floating-point equivalent to Joel Spolsky's excellent introduction to Unicode. In doing so, I learned quite a few things about the intricacies of the IEEE 754 standard, and just how difficult it is to compare floating-point numbers using an epsilon. If you find any errors or omissions, you can suggest corrections."

edadams sends in a story about the legal questions that are starting to crop up over property disputes in virtual worlds. A lawsuit in March 2008 that stopped one Second Life user from selling a virtual product created by another user marked the beginning of a significant amount of casework for several law firms, in large part due to the way Second Life's currency interacts closely with real money. (And yes, apparently the product in that particular case was for cybersex — did you have to ask?) "As transactions grow in volume, it's inevitable that disagreements will crop up. Linden says that although it will enforce its terms of service, including its ban on violating other users' intellectual property, it can't settle most disputes for users." A lawyer for one intellectual property firm handled a case in which the co-ownership of virtual real estate had to be determined, ending with a financial settlement given to two users who helped a virtual land developer run a group of Second Life islands. As virtual worlds get more popular and their business models more directly affect real-life finances, we can expect these legal issues to become more common as well.