Three Combo Boxes: Remove Options that have been selected in others

[Celcius]

I am looking to create a set of three combo boxes with around 15 options in each. If an option is selected in one of the three boxes, it is removed as an option from the others.

Dropbox Box 1 Options: 1,2,3,...,15
Dropbox Box 2 Options: 1,2,3,...,15
Dropbox Box 3 Options: 1,2,3,...,15

User selects option 1 from Box 1:

Dropbox Box 1 Options: 1,2,3,...,15 -> Selected 1
Dropbox Box 2 Options: 2,3,4,...,15
Dropbox Box 3 Options: 2,3,4,...,15

User selects option 2 from Box 2:

Dropbox Box 1 Options: 1,3,4,...,15 -> Selected 1
Dropbox Box 2 Options: 2,3,4,...,15 -> Selected 2
Dropbox Box 3 Options: 3,4,5,...,15

That would be great, and to make it perfect, add on this option.

User changes Box 1 to select option 3:

Dropbox Box 1 Options: 1,3,4,...,15 -> Selected 3
Dropbox Box 2 Options: 1,2,4,...,15 -> Selected 2
Dropbox Box 3 Options: 1,4,5,...,15

So if the user changes there mind before submit, it repopulates each box with the proper items.

Cheers

[Sterling Isfine]

I am looking to create a set of three combo boxes with around 15 options in each. If an option is selected in one of the three boxes, it is removed as an option from the others.

http://scripterlative.com/files/selectunique.htm

[Celcius]

Brilliant, thank you very much. Works exactly as needed.