If anyone is going down to Penang on a visa run you can go over to Medan Sumatra by ferry and take a bus up to Lake Toba. We stayed at the Hotel Carolina in Tuk Tuk for 16,500 rupiah a night (75 baht) in a large bungalow with two beds, bathroom, and table and chairs. We did not need a fan in the bungalow and kept the windows closed, this was in April. The hotel is great with a large screen tv, nice restaurant, lawn chairs by the lake etc. You can swim in the lake and check out the great scenery, you can take the ferry from Parapat over to Tomock also. Great break from the summer heat.

How long does the trip take from Penang?looks like a nice alternative for a change,also are there any more upmarket resorts available

Ferry over to Belawan/Medan was 4 hrs. and then about 1/2 hr. into Medan. From Lake Toba (Parapat) I believe it was 4 hrs. by minibus, big tourist buses might be faster. Out in Ambarita (5 kms. from Tuk Tuk) there is a swanky hotel called Sanggam Resort Hotel with rooms starting at 100,000 rp according to my book.