Just to get the ball rolling, I will go on record as loving single shots and lever guns.
My single shot collection consists of:
4 Ruger #3's - 223, 30-40 Krag, 375 Winchester, and 45-70. All except the 223 wear #1 wood, which makes them #2's or #13's I guess.
H&R Target in 38-55.
Ruger #1 in 375 H&H.
Encore Frame with barrels in 243, 350 Rem Mag, 444 Marlin. Have a 30-40 Krag barrel on order.
3 Contender frames - Pistol barrels in 35 Rem Rimmed and 444 marlin. Carbine barrel in 22 LR.
I think thats it for me.