When we moved from our apartment into our house, I had no real way to display my collection.  It was constantly growing and I wanted them to be displayed in some organized fashion.  So the first major display started out life like this.
(Click on each pic to expand)
After being in our house for over 4 years we wanted to change the way the house looked.  The walls were too apartment looking and we wanted it to be OUR home instead of what the last folks had.  After painting, changing the carpet, and adding curtains to the room (to the whole house actually), the above display just didn't fit in with the new look.  So we replaced it with this.
(this pic you can mouse over to see what is what)
We wanted to give it a little more flare, so we added lights to each space so it could be seen easily in the evening and give a touch of class to my geekiness.
You might be thinking that he's running out of space already.  Actually not.  Several of the sabers in the cabinet are duplicates, and I've been slowly weeding the collection of them.  Some I'll be keeping but moving to a different location in the room when Master Replicas makes them (i.e. Qui-Gon, Obi-Wan Ep.I, ect).  Others I'll just sell.
This is the Vader.  He's the center piece of the room.  Off to the right of the Vader is a grey table that will be replaced with a Stormtrooper mannequin soon.
A close up of the 'temporary' grey table.  The mini collection is here.  Then up front is a Vader ESB made from a Larbel MPP replica as well as a ROTJ Vader made by SD Studios.  Above the two lightsabers is a resin Stormtrooper blaster that I use when I suit up as a stromtrooper.  Under those three props is a Iranian mat that a friend of mine who is a U.S. soldier in Iraq sent me.

On the back of the table are two Vader helmets.  On the left is a 1977 Don Post.  To the right is the Riddell mini Vader ROTJ helmet.  Left of the Don Post helmet is two more full sized sabers.  One is a Graflex Luke ANH lightsaber and the other one is an Obi-Wan TPM lightsaber.
Vader has been a three year project in the making, and is almost complete....finally.  Parts came from very talented artisans from around the U.S. and Canada.  The mask is made from fiberglass and is a replica of the helmet used in The Empire Strikes Back.  It has metal grills with amber lenses like the original helmet.
The armor is three pieces, the main front piece and the two separate shoulder pieces.  This too is made of fiberglass.  The leather suit is a three piece set.  The cod piece and gloves are separate pieces and are also leather.  The belt is a black leather belt with 2 metal boxes with electronics.  The green buttons and red LEDs light up.  Hanging from the belt is a Vader MR ESB lightsaber.
The cape and robe are made of wool with the cape having a satin lining like the original costume.  The shins are made from ABS plastic and the boots are leather German military boots.  The only thing I'm missing is his chest box.  That *should* be coming in a few months.

All of these parts are on a 6'8" posable mannequin.  Chest, shoulder, arm and leg lengths and diameters are all the same as the actor David Prowse (Darth Vader for those of you who didn't know) measurements at the time.
This is the completed Vader and Stormtrooper.  The stormtrooper is 5'10" tall, so that gives you an idea of the size of Vader.  It doesn't look it, but Vader does have the saber on his belt still.
The ever growing mini collection among a few other items.  A non licensed Maul, Obi TPM, and a couple of different Qui sabers (full sized).  Another new item is the stormtrooper comlink from ANH (just below the mini Vader helmet).  Like the sabers, it too is 1:1.  And then for fun, there's also Yellow M&M as Vader!
An updated pic of the 'Vault'.  A few things that's changed from above...the Vader ROTJ Graflex was replaced with a MR Vader ROTJ SE, Luke ANH Graflex replaced with Luke ANH SE, MR Obi ANH replaced with Anakin AOTC SE, MR BD Maul LE replaced with Vader ROTS LE, MR Anakin ROTS SE replaced with MR Obi ANH LE, Luke ESB Graflex replaced with MR Dooku ROTS prototype, Qui-Gon TPM replaced with MR Qui-Gon TPM LE, Maul TPM replaced with Luke ESB Graflex and Luke ANH Graflex,  Windu TPM replaced with Vader ROTJ Graflex, Obi ANH replaced with Windu TPM, MR Vader ANH LE replaced with Obi ANH and the last slot was filled with the MR Vader ANH LE.

Up on top is the start of my ROTS helmet collection.  The one on the left is the MR 212th helmet (Obi's ROTS troops).  However it's got a little bit of a twist...I have a weathering job added to it to look like it was on screen.  I'll try to add pics of it soon.  To the right you'll see an empty stand.  That's the stand for the MR Special Ops/501st troops/Anakin's troops.  It's currently getting it's weathering job.  Pics to follow...