Download papercraft models of a manor, the battle hearse car, coffin boxes, midieval helmets, zombie, vampire and skull masks, board games, dice sets, pocket monsters, chess set and more. Get them at the paper toys section.
Ravensblight

Are you having a hard time building the complicated models that I have posted? You'll have no trouble building these. You can download the SD(Super Deformed) models of 2 race cars, a spitfire airplane and 2 tanks. Each model has 1 page of parts. Just check the "Free Download Zone" at the right side of the site.
paper-pro

This one is very similar to Disney Experience. You can download those beautiful models on top. Ray Keim is in the process of designing the Phantom Manor so don't forget to check the site every once in a while. He recently released the Conservatory Coffin which has animated parts. A simple lever allows you to simulate the desperate attempts of the confined ghost to lift the lid.
Haunted Dimensions

It's time to build some fish papercrafts. These beautiful models come in different colors and sizes. Download 13 fishes plus a stand. Built models vary in sizes. The biggest(Ito Japanese Huchen) is 33 cm long and the smallest(Oshorokoma) is 26 cm. Click on the "Paper Trout" to get to the download page.
AMAGO

Finally, a crown fit for a king like me...lol. You too can be king by creating this simple crown model from the "King of Bavaria."
Get your crown here your Highness.

I'm not quite sure what these are but they're definitely cute. To download these models, click on Spiky baby or Mask Hoody. Click "open a box" then click the picture to download the model. Click "back" then click "open a box" again to get the remaining models. The models appear at random so be patient. I got 20 designs including the box for Spiky and 13 including the blank template for Hoody. Can you get them all? Goodluck!
Shin

Ain't that building beautiful? That's the Mullet Hi-rise model from Sim City 3000. Highly detailed with some very small parts. You have to print 16 pages of parts. You can also download a church, the simple "Kame House" from the anime Dragon Ball and other buildings from Sim City.
Paper Buildings

You have probably heard all the buzz about this really cool gadget. Have this phone ahead of everyone. It may not be the real thing but hey, it's still cool. Pretty easy to make.
iphone

Want to build an armada of spaceships? You can now do so as this site offers lots of papercraft models for downloads. To those familiar with the game Homeworld, you can create fleets of ships from different factions like Kushan, Taiidan, Hiigaran, etc. Highly detailed and very easy to assemble. There are also Star Wars models. Files are in pdo format.
Erick's

Look what we have here! Two uniquely strange but beautiful papercraft models. These came from the movie Howl's Moving Castle that was released about two years ago. The first model is available as a papercraft book and is very difficult to find. Thankfully the second one is available for download. It was released by epson Japan in 2004 but they took out the link a couple of months ago. This was uploaded in another blog(paperkraftblog) but the last time I checked, the download expired. Fortunately, someone uploaded it again. Get it while it's still available. It's about 49 megabytes in size and has 26 pages of parts.
Howl's

You can download two small tanks from this site. The T-34/76 1941 and the Panzer Kampfwagen IV. Each tank has three pages of parts.
icm

Navy ship papercrafts can be very hard to build due to the very small parts that are included. There are many models available on the web but most are difficult to assemble. The JMSDF Aegis Equipped Destroyer "DDG173-Kongo" (1:268) papercraft(11 pages) is one of the least challenging models to build despite its complexity. You can also download the Oyashio submarine.
PMS

This site offers beautiful papercraft models of cars and warplanes. The files are available in pdf, pdo(wherein you'll need the pepakura viewer) and lzh files(get alzip). Just click in the papercraft link. Enjoy!
saturn

Build modern day warplanes like F-20 and Mig-29. The site also says "All model are designed to be able to fly !." I'll see that for myself when I build one. To get the models, click on the link with a yellow highlight for parts and the picture for instructions. The password is ojimak.
ojimak

Third update for today. Cool models for anime lovers like me. Files come in pdo files so don't forget to download the pepakura viewer to open them.
dead link

This site offers many (neko)cat-inspired models of anime and robots.
Asahi

For those who like airplane papercrafts, here's a site that offers WW aircrafts from Japan, UK, US, Germany, etc. There is usually one or two models available from time to time. To download a model, right-click on the pink bar and "Save target as ..." The password is simply the designer's name in all lower-case letters.
trotskiy

Here's a very nice house model. Easy to build and only five sheets of parts. Marvellously detailed exterior and interior with working doors, removeable roof and recessed windows. Even the fireplace is modelled along with a leanto and pile of logs.
HOVEL