There are a multitude of terms that may be spelled in either hiragana or katakana; the names of animals are a ready example that comes to mind. (e.g., オオカミ/おおかみ "wolf") Normal Japanese words may also be spelled in either hiragana or katakana for special effect. A comparison with uppercase/lowercase Latin is not perfect but sufficient.
The hiragana / katakana mapping seems like a straightforward operation, yet it is not happening in major search engines. (See T173650#3580309 for examples.)
[Description edited from comments on T173650.]
Example mappings: