[houseofshards]

Cool ! At some point, you could also consider building an index: retrieve "possible candidate corrections" by issuing a query against this index, and score the candidates using some combination of features (such as edit distance, phonetic similarity etc).

[castell]

As you mentioned, phonetic algorithm like Double Metaphone (stored e.g. in an SQL database) gives you probably better results (if you order the results by its score).

[gingerlime]

I was also wondering about using phonetic matching as a substitute for spell checking.

I guess one downside to phonetic matching vs spell-checking would be that you're not really telling the user that results are shown for a different term from the one they entered?