Here is a rarely known secret (well, maybe not much of a secret) involving HUDs:
world
maxx = 10
maxy = 10
maxz = 1
obj
icon = 'Test.dmi'
client
var
list
test = new()
test2 = new()
New()
..()
var/obj/O = new()
test += O
O.screen_loc = "4,4"
O = new()
test += O
O.screen_loc = "4,5"
O = new()
test2 += O
O.screen_loc = "1,1"
screen = test
sleep(10)
screen = test2
sleep(10)
screen = test
Does the code work? Find out for yourself (may need to supply your own test icon) and see a changing screen. :P
Those who were experienced with DM I bet know this secret. Screen variable has already known as a list type for clients, but works just like a good old normal list with specialties. While others may have already known about it, I'm willing to share it with ya for those who want it.