Ricky Gervais:
"Disco Inferno" (acapellla The Office Uk Remix aka The David Brent Dance) - The Trammps
https://www.youtube.com/watch?v=A_sY2rjxq6M - the originall
https://www.youtube.com/watch?v=p6Eaz-1_3iA - from The Office (starts at 3:12)

(classic moment from The Office UK)


Shawn Mendes;
"Guitar Man" - Bread
https://www.youtube.com/watch?v=CpOjQvADLG4

(though a celebrated pop star, he does play some good guitar.)