The Ulster museum has recently had a £17 million facelift. It's well worth a visit. It's right next to the compact Botanic Gardens and historical Queens University so you can do all three together.
The 'in your pocket' series of guidebooks are well worth recommending. The list of places is limited, but they are written by locals and are updated every two months. Even better, they are free and can be downloaded from the website.
The Belfast edition in booklet form is also free in the airport and other tourist locations.
In the light of the possible flight disruptions due to ash, it's worth knowing about the 'rail & sail' offer between Belfast and Scotland. You can book a train & ferry between Belfast and Glasgow/Edinburgh for £25 each way. Separate train and ferry tickets will almost cost double.
Train to other parts of the UKwill cost a little more but again far cheaper than if you get the tickets separately.
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