MurasakiYama has very different noodles from many other ramen shops, at least for tsukemen, they are almost as thin as somen, whiter, and more stiff, sort of like the noodles you typically find in Hakata tokotsu. The broth is soy and fish, with a fair amount of oil floating to the top, and hints of sesame oil and yuzu. It's a very flavorful and rich broth, and well cut not-too-fatty pork that was lighter on one side and darker on the other, almost fillet/loin, separated by a strip of fat that melted nicely into the broth. For ramen, the "purple yukari" in the upper left of the ticket machine screen is the store-recommended one. This place also has the first "fully" electronic ticket machine with a color display and a voice even, that I have ever seen, it welcomes you with an "irrashaimase!" when you approach it. The long counter in this clean and newly opened store (Feb 08) is well-lit and comfortable. The area around JR Tamachi station is not normally known for nightlife or restaurants - it's hidden in the the back streets of Mita near Tamachi station but it is worth it.
Ikemen blog with excellent pics
Diddlefinger Map (English labels)