Locating unicode chars in DB

This is an interesting one from a customer:

If you suspect that a field in an Oracle DB is having wierd unicode non-english chars, how do you confirm it? Sometimes these chars will be translated as valid English chars and cause all the more confusion. The answer is to use the asciistr function. This function returns all the chars as ascii strings...and unicode chars as escaped hexadecimal values.

E.g: select dep_id, asciistr(ALIAS) from gp_dependent where asciistr(ALIAS) like '%\%';

Its quite useful, note the opposite of the above is the unistr function. This one takes hexadecimal values in a string an converts into a Unicode text string.