I really wanted to give Kiraboshi a "Recommended", but something is just missing for me here, and it doesn't justify the lines I've seen in pictures. The place is extremely cramped, the waitresses were slightly falling over each other, one of them actually dropped a rice bowl into a customer's lap while I was standing in line. The water machine takes almost 30 seconds to dispense a cup of room-temperature water with no ice. The tsukemen is standard tonkotsu gyoukai, but they put an amount of cabbage on top and then coat it a bit more with a special brown fish-based sauce, either saba (mackerel) or katsuo (bonito)-based. The line was about 10 people when I got there. Most shops of this high ranking on Supleks (68) will also have a high ranking on other sites such as Tabelog, this one does not (3.14), as of this writing. They also offer a special "yamitsuki" (addictive) "change Jiro" topping for 100 yen that presumably makes it taste more like Jiro. The spice tubes there in the picture looked like they had been sittng there for ages.
Zatsu Blog with better pictures than mine