What are your favourite niche price comparison websites?

I am planning to launch a price comparison website for a niche but want to benchmark it against some good examples and gather some more inspiration of interesting niches.

It's impossible to compete with the big guys (e.g. airline tickets or insurances) so wont be interested in those, but what are some niche purpose price comparison websites that you frequently use/are popular in your country (e.g. finsing the best pantry staple deals, comparing EV charging costs, etc.)?