There is at least one very simple response. Set up some deviant CIX, say IX195-8, let everyone with a shortish 195/8 prefix connect to it either directly through their own provider, or indirectly through some tunnel, and have IX195-8 announce reachability of 195/8. That is, in short, altern topology to meet addresses when the converse is too hard. KRE detailed that for the general case, but it would be even simpler in the case of RIPE, since all the allocated network numbers are in the same geographical area.
I still think it would be worthwhile doing a top-down experiment with this sort of address structure around an easily aggregated geographical area, say the San Francisco Bay Area in northern California. I brought the idea up about 6 months ago and it floundered due to disinterest, but it still seems to be viable.
However, as Andrew w/UUnet pointed out some time ago, you end up providing transit in this way. If the goal is to only announce 195/8, any provider numbered in that block that is dual-homed with this "deviant CIX" and some other provider suddenly starts providing transit for the entire "deviant CIX". I highly doubt that this is desirable. Dave -- Dave Siegel President, RTD Systems & Networking, Inc. (520)623-9663 Network Engineer -- Regional/National NSPs (Cisco) dsiegel@rtd.com User Tracking & Acctg -- "Written by an ISP, http://www.rtd.com/~dsiegel/ for an ISP."