A neat trick I didn't know

I suspect everyone else knew this one, but it was quite handy for me.
We had to rename a bunch of JPG files to jpg.  There were some errors.  Some experimenting and a lucky guess made me realize that someone had created a few files with a name like style111.jpg<space>.  That is, before saving the file, they'd hit the space bar or something, so I'd see two style111.JPG but one would actually be style111.JPG<space>.

I fixed them by doing ls with a ' ' at the end, eg ls *JPG' '.  However, afterwards, I found what I think would have been an easier solution, the -e flag of cat.  It puts a $ at the end of the line. 

So, had I done it that way, I could have gone ls *JPG | cat -e and I would have gotten

style1111.JPG$
style111.JPG $

and all would have been clear from the beginning.

Anyway, I thought that was pretty neat, and thought I'd pass it along for those who didn't know it.