Great value on flights to Indonesia, Philippines and a night in London during the Summer holidays for only €678 return with all bags included! This deal takes advantage of a fantastic deal flight deal with Philippine Airlines from London Heathrow (for €588) and combining them with Ryanair flights to Gatwick (for €90 with bags). There is a bus that goes directly from Gatwick to Heathrow for only £12 to connect you between the airports.
There are a few dates for this deal from London to Bali and then Manila and then returning back to London. Below is a list of sample dates then just book Ryanair flights and give yourself plenty of time to grab your bags and transfer to Heathrow Airport.
Then combine the above deal with Ryanair flights from Ireland. Below is an example from Dublin. Please note that the flights are separate tickets so please allow plenty of time to get from Gatwick to Heathrow as if you miss one flight you miss them all!