I love this one and use it all the time, especially using the special case when your command can take multiple filename arguments and they come last. xargs will glom as many as it can into a single command before overflowing the max command line size, which can be faster than starting many processes. Grep is the best example:

      find . -name something | xargs grep -C5 search_string

(added the -C5 for context lines)