Four new businesses are filling the empty spaces at Rockville’s Federal Plaza, starting with ice cream and ending with tacos and sushi. Mimi’s Handmade, opening its first Maryland location, is almost ready to start scooping in the former Yogi Castle space. Look for unusual flavors like roasted red pepper, sour plum and passionfruit honeybee. (Click here for more on Mimi’s.) A couple of doors down, Good Feet will be relocating from its longtime home at Wintergreen Plaza. Good Feet, which sells its own line of arch supports, is expected to open this winter. And as we reported last week, the former Chuy’s space will soon be filled by two different eateries: a taqueria and a conveyor belt sushi restaurant. (Click here for more on that plan, which should come to fruition next year.)