can I do this?

In the course of recording songs--there are sections where the singing is tremendous and I just dropped all the music but the vocals. Can anyone think of any pop tunes where this has been done? Thank you Jim

Has been done in rap music long time ago. When I recorded some hip hop acts back in the 90's they were copying that same effect heard on their hero's recordings. Don't ask me exactly what artists have done it because I don't remember not being a hip hop fan, but I remember muting the backing tracks for a few bars at a time during mixdown.

I do exactly that in 2 of the songs I'm doing now. Three, actually, come to think of it. Not for too long, some beats or a measure or so. Doesn't seem remotely unusual to do. But so what if it was?

pretty common technique 

First song that came to mind: Listen at :45 I agree with Richie though. If it sounds good in the song then do it.

Those are called hooks (not that anyone here's interested in things so mercenary.)

Disregarding the fact that this particular thing has been done before, one could always go for a simple proof by contradiction: So, I propose that you cannot do anything unless it has been done before. Now if the above was true, we wouldn't even have any music at all.

Can you imagine BB King being concerned about making sure that he used a "new" chord progression or guitar lick? Or Beethoven worrying about using unique instrumentation? Ha!

That probably never happened :) On the other hand, we should be grateful for the first guy who came up with the idea to use a whole bunch of violins at once instead of just a few, or whoever it was that first thought "hey, this guitar actually sounds kinda cool when the signal is completely distorted", or "OK, so on this track I'll scream rather than sing"... ...etcetera.

acapellas are great. A chorus at full tilt going into an acapella repeat can be quite dramatic. Often modulating when it comes back in. Songs can start acapella too. A little instrumental intro then the first verse or half with just the vocals can be quite effective.