No way I could choose just one. But here are some of my favourites. Pictures were about a week ago.
'Alakazaam' - not sure this is a mini. It may be "small" I don't think of it as a mini, but I like it. It's still in a pot and I've had it about 3 years.
'Atom Smasher' is an interesting yellow mini that was a gift two years ago.
'Baby Bunting' is a fast-growing, blue mini. This is the one that spawned 'Cameo', 'Cherish', 'Hope' and 'Pandora's Box'. I have one division in the ground and one in a round trough with the rest of the family.
'Blue Mouse Ears' is, IMHO, the best of the family. I have several others, but have found many are really unstable. Most of the white-centred ones I've owned, except for 'Pure Heart', have quickly reverted to solid blue. This one grows fast and I have another division in the ground. This particular plant was divided in spring to keep it small enough to get the other mice into this trough.
'Country Mouse' lives with my other "mice" but it's from an entirely different family. It's also one of my favourites.
'Cracker Crumbs' - this particular division lives in a pot in a trough, though it's getting too crowded and I'll need to divide it. I have more of it in a border in the back yard, but I've found it makes a so-so border - not as full as I'd like.
'Dragon Tails' - is a delightful yellow mini.