If you need to meet with people over a computer, its hard to beat the ease of
Join.me. Its less expensive than GoToMeeting & easier to deal with.
If you meet in person, the best pitches are run from an iPad. You can project your keynote or you can actually sit next to the person to slide through materials.
Populr also works well sending pitch materials. Prospects want to see things to deal with their objections & Populr lets you send over information specific to their objections or hot buttons. You can include files, videos, images, and even embeds.
ClearSlide is good when you need to send a deck. Oddly enough, it also includes screenshare. The best use is when you want to send a deck & track if the person looks at it.
Uberconference is awesome when you have multiple decision makers that need to participate in the conversation. It will schedule the call, send info to all participants, and even record/transcribe what was said.
** Tip: Highly regulated industries are still in the stone age, so some of these may not work. You'll need to stick to email & attachments and pray for your buyers to catch up.