Two cents' worth
An individual's opinion.
This expression is now used in the UK, even though not many people here know what a cent is.
'My two cents' worth' (or 'two bits' worth') implies that, in order to express and opinion, a small charge is levied. This could well be a simple notional charge and not related to any actual payment. It has been suggested that 'two cents' was the minimum wager required of a new player in order to enter poker games. There's no documentary evidence to support that idea. The US version of the phrase is pre-dated by the British 'two-penneth' and there's little reason to believe 'two cents' worth' to be anything other than a US translation of that. The card-playing origin of the phrase could just as well apply to the British version but, without evidence, that's merely speculation.
The earliest example I can find of the US-variant phrase in print is from the Olean Evening Times, March 1926. That includes an item by Allene Sumner, headed My "Two cents' worth".