Couple of days ago I checked the Emirates pricing (on their website) for a DAC->LHR RT ticket in September. Ouch at USD1300+. But here is the interesting part. If you travel on the exact same days Kolkata->LHR, the price is an amazing Rs. 35000+. Almost half!
On the plus side, looks like the Dhaka->SE Asia route airfares are showing signs of thawing. Singapore airlines had a large ad in the Daily Star today advertising RT on DAC->SIN for all-inclusive USD 368 (down from 500+ they were charging before.) Also, Air Asia is offering low fares to KL, and I believe Malaysia Airlines has been forced to lower their DAC->KL fares because of this.
Also, there is a fare war afoot in the Dhaka->Kolkata route, with fares as low as Tk 5700 (USD80) round-trip on Jet and Kingfisher. I think one of the Bd airlines also got in on this fare war. But you have to book far ahead.
I hear that with Kolkata fares this low, you can do a RT to Bangkok for Tk 18000 or thereabouts if you route through Kolkata. This is almost half of what Thai charges for their DAC->BKK direct fare.
But maybe there is a proverbial sucker born here every minute, and the Emirates people have figured out who it is?