Northern zone pushers, whats worked for you?

I have been compiling my list of future plants for my property (usda zone 5) and whenever i see a plant thats considered hardy to a certain zone, usually if i do some digging ill find someone claiming to grow it further north.

So my question to those on here growing perennials, what have you grown successfully in a colder zone than its considered hardy to? specifically looking for stuff rated to zone 6/7/8 but also stuff you have grown in zone 3/4/5.

I know theres some zone pushers on here

It really really depends on your micro-climate I'm 7b but I cannot grow things that should be fine in 6 or 5 because we're damp, get no snow cover, no sun and get high wind. A lot of things you can get through the winter by having them in pots and moving them into the barn over winter, Rosemary and Sage have to have that treatment here, others like Artichokes can be covered in straw and survive.

We lived in north central MN for 4 years. Our coldest temp as minus 53 ( I am not talking wind chill).  We had few serious problems with orur garden other than rocks and pigs getting out from time to time.  Root crops did well. Getting tomatoes to ripen before a frost was always a challenge.  Fortunately, we lived on a hill that helped with the frosts.  We also used a lot of Epsom  Salts to spread the ripening.  If I had to do it again ( I have moved to zone 6.5), I would build a high tunnel.