A cloud generator was the first thing I thought of programming when starting this.
I mean, the first version of the MOO will only allow you to open pages and see what words are the most common.
Then I can go from there.
Further implementation ideas:
Areas will be hierarchical - Similar to how DNS records are kept in real life, areas will belong to domains. For example: com, org, edu, info are primary domains. br, cx, it, uk, fr are also primary domains. A place such as "theregister.co.uk" is in the "uk" primary domain and 2 subdomains of depth. The www subdomain will be ignored for the sake of sanity. As a further example, the domain "forum.theregister.co.uk" will be inside the "theregister.co.uk" area.
Primary & Subdomains that do not return webpages will be safe havens - With the "theregister.co.uk" example, co.uk doesn't return a webpage, so it's a domain in which you can group up with other players before going into theregister subdomain. Primary domains never turn pages and as suh, com, org, eu, info, br, cx, uk, etc will be the topmost primary areas which you can go from.
Domain Teleporter - Everyone will start with this device. It will allow you to teleport up and down a given domain. Teleportation will be free in safe-haven domains, but they will either have a cost or a timer once you go into a generated area. For example, teleporting down from "uk" to "co.uk" will be free. Teleporting into "theregister.co.uk" from "co.uk" will also be free. But teleporting out of "theregister.co.uk" back up to "co.uk" will either have a timer or a cost.
Size of a given area/dungeon will be based on the number of valid links it contains - Forums will be gargantuan and very dangerous places. Same with search engine pages.
Links will be doorways generated from the words they contain - If the link is the site name, or if the link has no words that can be used, it will be generated based on random words (not present in links) from the site. Preferably nearby words for it to make some sense.
Offsite links will work as fast teleporters - For example, in "theregister.co.uk" there is a link to "reghardware.com". If you manage to defeat monsters guarding it, you (And anyone else inside the dungeon) will be able to teleport to "reghardware.com" with no cost in the page which it was linked.
Areas/dungeons will be persistent with a 24 hours timeout - As in, monsters & other challenges like traps do not respawn. For example, once someone clears "theregister.co.uk" anyone else going into it will be able to follow any links without any fights or costs. If the "theregister.co.uk" dungeon isn't visited for 24 hours, it will be deleted from the system (along with all it's internal links -and- subdomains) to save space and give players an opportunity to refresh pages with new information, thus new links, monsters, drops, traps, etc.
Players will be able to bookmark links and domains - If they are present in the exact moment an area is cleared out of monsters, they can bookmark it. Bookmarked pages should allow you to use your Domain teleporter to go to it with a lesser cost/timer (or free if you're sitting at a haven/homepage). This allows you to quickly reach links and subdomains present inside an area while you're in another. Plus, your Domain Teleporter will beep and warn you when a bookmark has expired, allowing you to refresh and revisit a place with a lesser cost. The number of bookmarks you can have is something we have to determine later.
The last player standing when an area is cleared can set it as his homepage - A homepage is where a player will log in. Players without it will log into the last haven they visited. If you go as a group (or others pop in while you're playing in it) and defeat an area/dungeon, the area will go in pvp mode after a minute or so. This means you should either leave or be ready to fight for it, as the last player standing in there that was present during the clearance of the area will have dibs on homepaging it. The moment a place becomes a homepage, it will respawn every monster/traps/etc but they will not attack the homepage owner, but will attack any other player trying to visit or claim it. Players will be able to upgrade their homepage's defenses as well, for example, capturing a fish and then placing it in their homepage, or giving his fighting whales some rainbow axes. This should make some sites a huge advantage. For example, homepaging "google.com/search?q=fish" will give you a huge advantage in everything fishy. Homepages will also not expire (unless the player doesn't log for like a month) and will respawn monsters over time to keep the defenses up.
At least these are my initial ideas for the implementation. The PvP & homepage idea came up while I was writing the bookmark idea I had. I think it fits very well and gives some fun pvp elements.