Inexpensive concordance

In the comments, Alexander Potyomkin mentions Textanz, an inexpensive ($$) word and phrase concordance program.

Word concordances can be easily done with an office word processor and spreadsheet; phrases are somewhat more complicated, as are comparisons across multiple documents. I can't tell whether Textanz supports lemmatisation, but it may be a good solution for folks who need to look for simple word and phrase co-occurrence without the hassle.