Section sponsor Scottish Friendly,
please visit them - ( and win a bottle of whisky). 
Mainly known for their Tax Free Savings Plans, they have an interesting history and background.
These are regular monthly savings plans.
Investment profile tends to be conservative - a managed fund or with profits approach. This is not a legal requirement, but more a result of tradition, ( and the fact they used to be obliged by law to adopt a low risk approach).
I expect to see some more interesting fund variations made available ( and indeed Family FS have already launched an Ethical Fund).
Pretty well everyone can find a place for 10 Year Savings Plan , with the simple proviso that you must be confident that you will invest for the 10 years.
It is a must have for higher rate taxpayers.
It is a very good tool for parents investing for children, as each child can have one, and by the time they get the money, should be sensible about it, ( great for university fees or house deposit or babe magnet....)
Charges - watch out for charges, and be careful about those with monthly policy fees. You are only investing a modest amount and even £2 is a lot out of £25.
Investment approach - make sure that you understand where your money will be invested.
Life Insurance - part of the package, but for the old it detracts from the investment aspects to some degree. ( Grandparents might be better paying towards a grandchilds plan than starting their own, but as always, ask your IFA).
Mutuality - most Friendly Societies ( all? being definite will only bring emails, but certainly most), are Mutuals. This means that they are owned by the policyholders, not shareholders, and that , after the expenses of running the society, all the profits go to the policy holders. If the society is efficient then this is good because you should do well. If the society is not efficient then you might end up benefiting from a demutualisation a la building societies. That said second guessing the future is always chancy and this should not be uppermost in your mind!
The other products that Friendly Societies offer are :-
1)Single Premium Bonds, these are not tax exempt, and should be looked at in the same manner as other Single Premium Bonds.
2)Critical Illness and Permanent Health Insurance, which are worthy of consideration when looking at these areas. You might find that a mainstream company is best, or that a Friendly Society is good for you.
You should be aware that FS policies may have an investment element, whereas mainstream policies are normally pure protection. When this is the case the premium for the FS will normally be higher than that for pure protection policies, and you should seek to ensure that you know whether it is better to combine the protection and investment elements, or keep them separate. The answer may be mathematically clear, or more of an emotional decision. Discuss this with your IFA.
Notes about our sponsor, Scottish Friendly. They are a mutual Friendly Society who use both Unit Linked and With Profits Funds and are very much in favour of people doing business through IFAs.