Key advice for where to start:<p>3. Exploit irregular network topologies. In the last 90s, most people assumed that dating websites was a "winner take all market" and Match.com had won it, until a swath of niche competitors arose (e.g. Jdate) that succeeded because certain groups of people tend to date others from that same group. Real-life networks are often very different from the idealized, uniformly distributed networks pictured in economics textbooks. Facebook exploited the fact that social connections are highly clustered at colleges as a "beachhead" to challenge much bigger incumbents (Friendster). By finding clusters in the network smaller companies can reach critical mass within those sub-clusters and then expand beyond.