They have a zipped, downloadable version right there on the front page.
For those baffled by this, let me 'splain:
In 2000, the publishers of Dungeons & Dragons released the third edition of that game. As part of the 3.0 roll-out, they announced that large portions of the core rules were going to be released as Open Gaming Content, and that any company or individual would be allowed to use and adapt those portions of the game mechanics to release their own product. They made those open portions of the game -- the System Reference Documents -- freely available on the Web, in the form of Rich Text Format documents for each individual chapter-chunk of rules.
A few years later, they released d20 Modern, primarily for games set in Industrial and Post-Industrial settings. The d20 Modern SRD includes d20 Future, which gives rules fo many of the tropes of classic Sci-Fi.*
Unfortunately... the RTF documents kind of suck. They're ugly, poorly organized, and the RTF format itself creates distressingly huge files. Many, many people have translated the main d20 SRD files into convenient, well-organized HTML documents, some of them downloadable for local reference, others strictly as an online resource.
Very, very few people have bothered to do the same with the d20 Modern SRD. The one that pops up most often on a Google search only includes the d20 Modern core files, and not the supplementary files that were released later.
The link above contains all of the d20 Modern SRD material, in a fairly readable and useful HTML format. It's also downloadable, so if the site vanishes or goes over its bandwidth allotment (it's friggin' geocities), well, here it is!
*Semantic Disclaimer: The use of the term "Sci-Fi", with its pulpish, B-movie connotations, rather than more "respectable" terms such as "SF" or "Speculative Fiction", is deliberate.