It seems since 10.4.2 or perhaps one of the security updates? that my airport connection appears to loose it's signal, yet the bars on the airport menu bar indicator still show full status, still everything, even apps that don't rely on an internet connection all hang, the only solution I have found is either turning airport off and then on again, or having to physically restart the powerbook by pushing the power button...anyone else experience this? Fortunately the restarting the airport seems to work pretty well.