My most powerful zoom scope starts off at 3x. It's a Schmidt & Bender 3-12x42 Klassik mounted on a Ruger No. 1A in 6.5x55 SE. The rest of my zooms are shorter than that mainly because I hunt in the southern woods and the majority of my shots are under 200 meters. I prefer not having too powerful a scope simply because it's easier to put the crosshairs on the deer or hog with a lower powered scope & the accuracy is more than adequate for the ranges I'm shooting at. Some of my favorites are:

Schmidt & Bender 1.5-8x42 Stratos
Swarovski z6 1.7-10x42
Swarovski z5 2.4-12x50
Nikon Monarch 1.5-6x42
Redfield Revolution 2-7x33
Leupold 3x20 Big Bore
Leupold FX-3 6x42

The only scope I have that has a longer minimum value is a Meopta R2 8x56 RD.