Craig and I were singing last night -- going through some old cover songs. We tend to stick to originals when we play out, but our playlist here at home includes lots of great tunes by some brilliant songwriters.
Singing Kris Kristofferson's "Help Me Make it Through the Night" is a good exercise, because besides being a sweet tune, it's written in a wide vocal range, with some tricky intervals - things I shy away from in my own melody writing.
Kristofferson and his then-wife Rita Coolidge do a very sexy version in this video:
Youtube link is here.