Joe Kraus makes his personal comparison starting a business in 2004 and 1993:

"I've been reflecting on how different it is to start a company in 2004 vs. 1993. While I still break out like a nervous teenager, which looks awfully strange with graying hair, at a professional level, there are three substantial cost differences that make it much easier to start a business on much less capital. I think this is a great trend for entrepreneurs and has a not-so-clear impact on the venture business.

Cost Difference #1. The tools to develop software cost nothing now.

Cost Difference #2. Hardware costs are approaching 0.

Cost Difference #3. Start-ups have access to global labor.

with today's ability to work with people all across the world comes the the great responsibility of needing to manage them to get what you want. It's going to change the required skills for successful entrepreneurs. Successful management ability early on, not just great drive and persistence, is going to become an absolute must."

I may add Cost Difference #4. Marketing works different nowadays - blogs are an ever increasing marketing power and (smaller) cost factor

Cost Difference #5. Enterprise Software Sales has gone ASP - there are many ways to reach customer besides the old-fashioned sales pitch (for some products at least)

Cost Difference #6. Communication Costs appraoch 0 with Skype and Skypeout

Cost Difference #7. Offices loose their value - small businesses are often virtual

Via emergic.org