The houses of parliament netblock is publicly listed:
Despite their unwillingness to reveal the UK parliament web proxies in an FOI request, wikipedia allows you to query for /24 blocks. 63 wikipedia queries later, and here's the list of every IP address that has made a wikipedia edit from the UK parliament netblock.
- 194.60.62.36 [7 found](h ttps://en.wikipedia.org/wiki/Special:Contributions/194.60.62.36)
- 194.60.62.35 10 found
- 194.60.62.34 15 found
- 194.60.62.33 34 found
- 194.60.62.32 7 found
- 194.60.62.31 12 found
- 194.60.62.29 22 found
- 194.60.38.29 8 found
- 194.60.38.28 26 found
- 194.60.38.27 8 found
- 194.60.38.26 17 found
- 194.60.38.25 2 found
- 194.60.38.24 1 found
- 194.60.38.205 15 found
- 194.60.38.204 10 found
- 194.60.38.203 19 found
- 194.60.38.202 22 found
- 194.60.38.201 6 found
- 194.60.38.200 3 found
- 194.60.38.20 1 found
- 194.60.38.198 2264 found
- 194.60.38.11 14 found
- 194.60.38.10 3655 found
Guess which ones the proxies are (Its not the high numbers, they're the old ones)
For an encore, here's the Prime Ministers office:
- 194.201.189.162 11 found
And for my final trick, the Government Secure Intranet proxies:
- 62.25.106.209 7585 found (gateway-101.energis.gsi.gov.uk)
- 62.25.109.196 2388 found (gateway-103.energis.gsi.gov.uk)
- 195.92.40.49 7977 found (gateway-202.energis.gsi.gov.uk)
- 62.25.109.194 4316 found (gateway-301.energis.gsi.gov.uk)
- 62.25.109.196 2388 found (gateway-303.energis.gsi.gov.uk)
- 195.92.206.244 17 found (gateway-403.energis.gsi.gov.uk)
- 195.92.206.243 92 found (gateway-402.energis.gsi.gov.uk)
Many thanks to @russss, who did a lot of the GSI digging.