This place has been around for years and is a chain restaurant all over Seoul and S. Korea. They specialise in pork bbq and pork kimchi jiggae. Their kimchi jiggae always hits the spot!
I recently tried a different place for kimchi jiggae that's very well known amongst Koreans called 은주정 김치찌개 (EunJooJung Kimchi Jiggae). It was really good, but not as easily accessible as 새마을식당 (SehMaelShikDang) which is everywhere - I'll probably end up coming here more often again!
What? 새마을식당 (SehMael ShikDang) - New Town Restaurant. Known for their 7-minute kimchi jiggae and thinly sliced spicy pork bbq. They have other pork bbq items on their menu along with dwenjang jiggae and noodles.
Who? Anyone who likes spicy food, pork bbq (but not necessarily samgyupsal) and kimchi jiggae. Very casual but delicious!
When? Everyday, 24 hours!!! It is a chain restaurant though so it may depend on which location you go to.
Parking? Yes - depending on which location you go to. At the Hannam location, you can usually just park in front along the sidewalk.
Cards Accepted? Yes
Where? Many many many locations. Find out the how to spell the area you live in in Korean. Then match the area with the list here and copy and paste the address into google maps: http://www.newmaul.com/newmaul/store_domestic.asp?shop_region=1
The one I usually go to in Hannam-dong and it's 24 hours:
서울특별시 용산구 한남동 85-4. 85-4 Hannam-dong
Directions: From Hangang-jin station, Exit 2, walk straight until you hit the main road. Turn right as if going towards Hannam-bridge. Just after the gas station (150metres), veer right. Keep walking straight, past the 4 way main street where SoonChang Hospital is, and then you'll see it on your left. It's across the street from Baskin Robbins and Kkangbu Chicken.