An important place untouched by travel portals to reach out to potential customers are Airports/Railway Stations. If Kiosks are made available at airport which provide instant hotel/car transfer and next day morning domestic flight reservation facility. It will not only provide convienance to customers but help in creating brand name awarness.
To begin with rather than having Computerized Kiosks just have toll free line directly connecting users to customer care service of portal. This way it will give you time to understand last-minute travellers requirement and change website process for suiting them when computerized kiosks are installed. Make sure kiosks have atleast 4 lines and you put one each at Arrival and Departure Terminal. I am expecting Departure terminal to generate more sales as compared to arrival terminal due to habit of flight delays in practise. It gives people time/opportunity to take care of their hotel bookings in free time made available courtsey the airlines.
Another area where travel portals can look at for bringing value to their customers. tieing up with lets say “XYZ Airways” and comming up with a co-branded card which gets mileage both on airlines and for shopping on the travel portal. But advantage is ability to access airlines lounge by getting ‘X’ mileage point with the portal. This way economy class travellers who are flying low frill airlines can take advantage of patronizing a travel portal and giving lot of business. Also it will help identify premium spenders on the site.