ROM is a mud server, ie it is a program that when running lets people connect to it and take the part of characters in a virtual world. If this makes no sense, then check out the FAQ for the rec.games.mud.misc newsgroup which provides answers to the more fundamental questions.
ROM is a server that is derived from the Merc code base, which in turn is a derivative from the original Diku code. The effects of this can be seen in question 1.4
The main developer of ROM (which was originally a mnemonic for "Rivers Of Mud") is Russ Taylor, though Brian Moore and Gabrielle Taylor have played a significant role in it's development, along with a number of other people, all of whom to which we owe a great debt of gratitude. Read the credits files in your ROM package to get more details.
ROM is currently in beta, but nonetheless provides a very stable and efficient code base with many notable features. There are by default 4 races, 4 classes, and the ability to customize which skills each player gets. There is a clan system which can be used to restrict pkill, and enough imm commands to effectively deal with running the mud, as well as handling troublesome players. There are several dozen areas provided with the stock package, so with usually little effort it is possible to have a fully running mud from scratch in a matter of minutes. This however, is the easy part of running a mud.
ROM is not, as most erroneously believe, a highly processor intensive program. A running mud on a pentium machine running Linux may typically use less than 5% of the cpu time. Memory however can be a consideration. The basic package has enough areas to use up a total of approx. 5mb of ram, but as more areas are added this can increase significantly. ROM is very efficient in it's memory handling, and as such the program itself is very compact in size indeed. The author's mud currently with 130 areas uses about 13mb of memory. Disk space requirements are also not excessive, with most space being taken up by object files created during compilation and again area files. A running mud with plenty of areas can live happily in 50mb of disk space.
The operating system requirement is linked with that of network connectivity. A DOS compiled ROM needs no network, as it supports only one user. When the mud is run on linux or Windows 95/NT however, a full time network connection is required if you seriously want to have your mud a public concern. Getting server space these days is much easier than several years ago, with many companies offering to host a mud on a machine at their site for a relatively small sum of around $30-$50 per month. Of course if you have the ability to set up your own full time server that's great, but avoid running a mud on a machine without the owner's permission.. you wouldn't be the first University student to get into major trouble for unauthorised use of computer equipment.
The most official places to pick up the unix package for ROm are from Russ Taylor's home page, at http://www.cmc.net/~rtaylor, or from the Hypercube site, at http://www.hypercube.org/tess/rom.
Alternatively, this plus windows versions can be found at the game.org ftp site, which has many other mud resources. For ROM look in: ftp://ftp.game.org/pub/mud/diku/rom/
In a word, 'NO'. ROM is neither shareware or freeware. It comes with specific licences that must be followed by anyone using the code. Being a derivative of MERC and in turn Diku, you will also be subject to the licenses for those code bases also. All the licenses can be found within your ROM package, and should be read before going too far into the ROM world. A good summary of the licence conditions would be: "Make no financial gains from this, and give credit where it is due."
There are more terms, for these read all the appropriate licence files. And if all this sounds strict, consider the effort required to write the 40,000 lines of code that is ROM. It doesn't seem too extreme to ask what is asked for the privilege of getting this code otherwise free. If you feel the licence conditions are too much to ask, then good luck with your own code base.
The question of copyright and just what it means, especially with reference to Rom does hit the Rom list frequently, the following is an attempt to answer the usual variations on this theme. For more information on copyright, the 10 Copyright Myths is a good document to start with, and it also has a number of useful links for further reading on the subject.
Yes. From various international copyright treaties, including the Berne convention, a piece of work that you commence by extending an existing piece of work will always be considered a derivitive of that original work. In somewhat plainer terms, your mud will always be bound by the terms of the Rom licence if it's development came from the Rom code.
The only way a mud is totally free from the Rom licence is if it's code was developed from scratch, with no reference whatsoever to the Rom source. This is the legal standing for any intellectual work, this is not mere invention by the Rom consortium.
By no means. In the same way that the copyright statutes protect the creator of original works, they likewise protect the changes made to such works. Any changes you make to the source are yours, copyrighted to you. You have the same rights and controls over your additions and changes as the Rom Consortium do to the changes they introduced into Merc. You can release the code publically if you wish, but only if you identify it as a derivitive of the Rom source. You can add any additional licence requirements to such publically released code, with the exceptions that you must both fully comply with all licences to which you are liable (Diku, Merc and Rom), and provide no clauses in the new licence that contradicts any of the provisions in the previous licences.
ROM is currently version 2.4 beta 6. Updates will be announced when they become available, so don't waste Russ Taylor's time e-mailing him asking when version 2.5 will be released. The answer you will get is doubtless "when it's ready."