This article [] was linked in the Reddit comments for this post - it goes into an explanation of bloom filters and then includes the code for a spell checker implemented with them.

[]: http://ipowerinfinity.wordpress.com/2008/03/02/bloom-filters...

Thanks for this link. Much more interesting than the article.

The idea would be to read in the entire dictionary and mark the Bloom Filter for each word. Then whenever you get a word you want to test, see whether all of the places it would mark were previously marked. If it misses any, you know it's not a word. Unfortunately, if it doesn't miss, you're only sure it's probably a word (with the worst case probability controlled by the number of hash functions you use).