Yep. I know the freeper who did the original research.
I think I do too, and I think I've been conversing with that person on a different forum.
I've been trying to figure out how Obama Jr and his mom could have traveled between Indonesia and Pakistan with ease and somewhat untraceable.
http://www.globalvisas.com/uk_immigration/uk_right_of_abode.html
UK Right of Abode
The Certificate of Entitlement to the Right of Abode in the UK, is a UK immigration visa service, which entitles a person to live and work in the United Kingdom without restriction.
Holders of this type of visa for Britain may enter and leave the country free of Immigration control and use British passport holder gates at United Kingdom ports and airports. Dual citizens are entitled to a stamp in their foreign passports, which will enable holders to enter the country without hindrance as though they were British Citizens.
It is worth noting that changes to legislation have resulted in this category of immigration service becoming partly redundant, as many people applying under this class are eligible to apply for Indefinite Leave to Remain in the UK (ILR), or permanent residency through British naturalization.
After 21 December 2006, people who already hold a British passport, or identity card which describes them as a UK citizen or as a British subject with this entitlement will not qualify for certificates of entitlement.
Benefits
Applying for the right of abode effectively results in a successful applicant being entirely free from British immigration control. This means that a holder does not need to gain permission from an Immigration Officer in order to enter the country and may commence living and working in the UK without restriction.
This route to the United Kingdom imposes no work restrictions like short-term UK visit visas, often referred to as travel visas or tourist visas and unlike skills based immigration services such as the Highly Skilled Migrant Programme or HSMP, this route does not require a points based assessment to qualify. Unlike UK business visas, candidates do not need to create jobs or invest in the United Kingdom and successful applicants do not need a UK work permit visa.
At Global Visas, we can help you to secure the most beneficial immigration service for you from the range of British visas for immigration and working permits available. Whether you need a short-term visitor visa or you wish to move towards UK citizenship, as a specialist UK immigration consultancy, we can offer immigration lawyer advice and services throughout the application process.
Duration
There is no time restriction placed on people immigrating to the UK via this route. The Certificate will remain valid for the life of the passport.
Eligibility
Who has the Right of Abode in the UK?
All British citizens automatically have this right. In the case of dual nationals, i.e. people who are citizens of more than one country, it is possible to get a Certificate placed in their passport.
This right may also apply to some people who are not dual citizens but are from a Commonwealth country. Commonwealth citizens qualify under the following circumstances.
If they are UK citizens:
If they were born before January 1st 1983 and have a parent who was born in Great Britain. (or a territory, such as KENYA)
If they are a Commonwealth woman and married a person before January 1st 1983 in one of the above categories.
(N.B. Pakistan and South Africa were not included in the Commonwealth before January 1st 1983 and as a result their citizens do not qualify)