I started this list a couple of weeks ago and figured I'd post it, so others can add to it as a reference:
Edirol UA-5
Switchcraft S760
Adaptaplug “M”
Outside Diameter : 5.5mm
Inside Diameter : 2.1mm
Inside pole : negative (-)
Input Voltage : 9V DC
Supply current : 450mA
Graham Patten DMIC-20
Switchcraft 761K
Adaptaplug “N”
Outside Diameter : 5.5mm
Inside Diameter : 2.5mm
Length : 12mm
Inside pole : positive (+)
Input Voltage : 5.6 – 8.6V DC
Supply current : 300 - 500mA
iRiver iHP-120
Switchcraft 860
Adaptaplug size “B”
Outside Diameter : 4mm
Inside Diameter : 1.5mm
Length : 11mm
Inside pole : positive (+)
Input Voltage : 5V DC
Supply current : 2A
Tascam DR-680
Switchcraft S760
Adaptaplug “M”
Outside Diameter : 5.5mm
Inside Diameter : 2.1mm
Length: 9.5mm
Inside pole : positive (+)
Input Voltage : 8V - 13V DC
Supply current : more than 600mA