Heathrow hosts the largest coach and bus station in the UK.
Hong Kong has buses and a busy ferry terminal.
https://en.wikipedia.org/wiki/Hong_Kong_International_AirportIntermodal transportation hub
To sustain the growth of passengers, the Airport Authority formulated a "push and pull through" strategy to expand its connections to new sources of passengers and cargo. This means adapting the network to the rapidly growing markets in China and in particular to the Pearl River Delta region (PRD). In 2003, a new Airport-Mainland Coach Station opened. The coach station has a 230-square-metre (2,500 sq ft) waiting lounge and sheltered bays for ten coaches. Many buses operate each day to transport passengers between HKIA and major cities in the Mainland.
The Coach Station was relocated to the ground floor (level 3) of Terminal 2 in 2007. The 36 bays at the new Coach Station allow cross-border coaches to make 320 trips a day carrying passengers between the airport and 90 cities and towns in the PRD. Local tour and hotel coaches also operate from T2. The coach station at T2 has shops and waiting lounges as well as a mainland coach service centre which gathers all operators together.
In late September 2003, the SkyPier high-speed ferry terminal opened. Passengers arriving at the SkyPier board buses to the terminal and arriving air passengers board ferries at the pier for their ride back to the PRD. Passengers travelling both directions can bypass custom and immigration formalities, which reduces transit time. Four ports – Shekou, Shenzhen, Macau and Humen (Dongguan) – were initially served. As of August 2007, SkyPier serves Shenzhen's Shekou and Fuyong, Dongguan's Humen, Macau, Zhongshan and Zhuhai. Passengers travelling from Shekou and Macau can complete airline check-in procedures with participating airlines before boarding the ferries and go straight to the boarding gate for the flight at HKIA.
In 2009, the permanent SkyPier Terminal opened. The permanent ferry terminal is equipped with four berths, but the terminal is designed to accommodate eight berths. Transfer desks and baggage handling facilities are included, and the terminal is directly connected to the airport automatic people mover system.
But all the transit that goes to that terminal seems to only serve passengers traveling to and from the airport, and not the general surrounding area. Then again, it's Hong Kong (geology plays a big role).
I clicked with baited breath. Absolutely nothing new unfortunately. If Metrolinx was so avid to move on this, they'd allow transferring through Pearson to the UPX from GO Routes 34 and 40 as an open ticket. But alas...they'd have to make good their word.