The finest edge you can get on any tool is with a strop or buffing wheel. This can prove difficult to do without rounding the bevel. In certain cases (such as with carving tools), a rounded bevel may be desirable, but with chisels and plane blades it is best to maintain a bevelled angle. A hard felt wheel is best for the task.
When dressed with a blade honing compound, the edge is noticeably sharper than most razor blades (Veritas® have electron microscope photographs to prove it). A medium felt wheel is still very firm, but is more suited to carving tools where controlled bevel rounding is desirable to give edge strength. A narrow, medium felt wheel is best for the inside of carving gouges. All of these wheels are bored for 5/8" diameter arbors, but a 1/2" bushing is provided with each.