I frequently use the system-wide floating (contextual) Dictionary application when working in Pages 08 (press Command-Control-D to activate the floating dictionary), but have become very familiar with a nasty bug: sometimes Pages 08 crashes outright when using the floating dictionary. It happens only when you look up one word, and then drag the cursor to look up additional nearby words -- single word lookups seem to be fine.
I have no cure for this (I hoped it would be fixed in 3.0.2, but no luck). It's pretty intermittent too, only happening on occasion. It seems to happen a lot on larger documents, though. Of course, the best key combination when using the floating dictionary is Command-S to save your work, and only then use Command-Control-D to use the Dictionary! This is now an instinctive key combo for me.
[robg adds: It took me a few tries, but I was able to replicate this bug on two machines, though I can't tell exactly what triggered it -- just at some point in time with the floating dictionary visible, Pages went beachball city, then bailed. I filed a bug against it (Bug ID# 5851856) just in case it hadn't yet been reported.]
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http://hints.macworld.com/article.php?story=20080403013121351