You can already do this in Safari in iOS without a Mac.
Just tap download (e.g a font on this site - http://www.dafont.com/) and then open in the local app of your choice. I use Transmit app as my local File system, or I save my files onto my Synology using the DS File app.
The problem is there isn't a proper download manager in mobile Safari - so you can't track the progress of large files - this is an area that I hope sees improvement in the future.
Thanks very helpful. i will try this out. Adownload manager would be very helpfully indeed