My favorite experience here so far was a night in early fall, sitting outside and enjoying a few beers with a friend after a bike ride. Perfect weather, great suds, and a lively crowd enjoying a blues band. Every town needs a place like this!
The Iron Post earns their stars with live music: most nights, some local group is on stage for a cover of $2-3. Of course, the quality depends on the group, but many are wonderful. They often feature student/faculty groups from the UIUC jazz program, which can be fantastic (especially the faculty groups). The calendar is on their website and is up-to-date despite the 1990s-looking design :)
Food is inexpensive but only okay, particularly compared with the Embassy next door (which actually has a grill). I believe they have an oven and a microwave only. On the plus side, their fries are baked (healthier but still tasty). They have a night where they grill steaks outside, something I've not yet experienced but would try.