I suppose it's currently rather off-topic to ask for advice about synagogues and restaurants, when someone travels abroad. There's indeed this product-recommendation tag in a similar vein. I think it would be extremely useful to create something similar to take advantage of community members all around the world. Mostly I'm thinking about providing information about:
- nusach (Ashkenaz, Sefarad, Mizrach, Ari etc.)
- available days and prayers (weekdays/holidays, mincha only etc.)
- location, contact if needed
Obviously it would be quite "administrator-intensive" to keep it tidy, but other sites on the internet tend to be out-dated.