The Welsh record scorer drew the curtain on his glittering 11-year international career against Australia on Saturday and capped his farewell with a 60th Test try.
Two of those tries came for the Lions against South Africa in 2009 and he scored a further six-times in non-capped games during the 2005 tour of New Zealand - including five in one match against Manawatu.
And while Williams admits he may not merit a place in 18 month's time but has refused to rule out making a comeback for a third campaign.
"I haven't been part of a winning Lions tour and that's something I would love to have done," said Williams.
"If the offer came then I would have to cross that bridge then.
"It's a fantastic experience and I will definitely be over there enjoying myself and doing something in other regards.
"I can't imagine I would be the best wing in Wales, let along Britain and Ireland, but the Lions is a fantastic occasion to be part of."
The pocket-sized wing has shaken hands on a two-year extension deal with the Ospreys that will see him through to the 2013 tour to Australia.
"I would like to end my career at the Ospreys," added Williams.
"Whether that's in a playing capacity or doing something else I don't know. Hopefully, we will have a chat about it during the next couple of weeks."