Can I remove grout from a tile?

Here is one tool. There are many others.
Grout Grabber - The Affordable Grout Removal Tool

Smearcase, is that a special blade for a reciprocating saw or is the whole tool the grout grabber?

This site refers to it as a blade for reciprocating saw. It would take some care to avoid chipping/scarring edges.

Whoops, forgot the link!

Amazon.com: Grout Grabber GG001 Grout Removal Tool for Most Reciprocating Saws or Sawzalls: Home Improvement

Great if you have a recip. If you don't but you do own a Dremel try this Dremel Grout Removal Attachment Kit and Grout Removal Replacement Bits $22.00 Both look like they'd do a good job.

I don't know which would be worse, trying to get down with the Dremel or trying to crouch and keep the recip. Saw on line.
That Amazon link has a lot of comments from people who have used the Grout Grabber.
Mixed reviews.

The more I think of it , I hate removing grout no matter what tool. The only one I did lately was my own bath and that was a really tight line that you could pretty much shatter with a sharp utility knife. I guess I just like new tools and ideas, not necessarily buying and using them.