IIRC, the US travel embargo was lifted in February, when Libya was demoted from the 'Axis of Evil' to the 'Axis of a bit Naughty'.

This is intriguing - from poking around, you can get TIP-HKG in BA F for £900 or TIP-SIN in SQ F for £1000 (GBP). The fares are listed on opodo.co.uk, but they seem to throw an error when you try and book them.

From looking around, you can transfer at TIP without a visa, as long as you stay in the airport. This makes it very tempting to do, but I'd like to hear someone else's experience of doing the same before I try it...