Like many subjects there's no magic solution and you have to figure out what works best for your organisation vs the cost and complexity.

DR and HA are different subjects anyway.

At the most simple level failover clustering and log shipping work well - I've usually found the sql server ( database ) solution is the simpliest part of finding a DR/HA solution for a whole application.

Handling data feeds, web sites, application tiers, web services, reporting, exports, logins, users, AD etc. are usually more of a challenge.

Oh and usually the "how much?" when you provide suggested solutions!