Yes, there are the ISO 25 films already mentioned. There's also Ilford Pan F at ISO 50.
Kodak T-Max 100 (100TMX) and Fuji Acros 100 have very low graininess, and ISO 100 ratings. They are both very good for great enlargement.
There are a few films that are similar to Technical Pan: document copy films that can be used for normal pictures. These tend to have an effective speed around EI 12 or EI 25 when developed for pictorial use.
Flaws that are not noticeable at low enlargements may become noticeable at high enlargements. Three of the things to watch in that respect are diffraction, camera shake and depth of focus. Use a tripod, or a higher shutter speed than you would normally use, and assess depth of field using the lens markings (or table) for at lest one but preferably two stops more open that the aperture in use. For example if you are shooting at f/8, use the markings for f/4. Don't stop down too much, unless you are happy trading depth of field for overall softness caused by diffraction.
Depending on the quality you want, you may want a very good scan at 6000 ppi or higher, either from a high end flatbed like a Creo iQsmart3, an Imacon or a drum scanner. I don't mean a "6000 ppi" scan from a consumer flatbed. I rent an Imacon 949 for the 35 mm film I want to scan at 8000 ppi for large prints. Of course it could be printed optically.
Best,
Helen