Bound-to-be-useful tidbit from MacOSXHints user giskard22:
To tell Spotlight to re-index, open Terminal and type:
sudo mdutil -E /sudo mdutil -i on /
this photo has nothing to do with technobabble. Well, unless you're talking about how it appears on your screen.
I had somehow corrupted my Spotlight index weeks ago, but was too lazy to look up how to recreate it. Until now - it is busily reindexing (5 hours for my intra-net drive).
John Siracusa has an in-depth look at Spotlight at ars technica if you are interested.
Nice photo though, the tree shadow is particularly fine :)