Search engine list
(in no particular order)

Everybody

The Search Engine List



Same Origin Policy

(controls how scripts (and iframes) interact with home domain)
Straight from the horse's mouth

Google
Yahoo

Open Source

OpenSearch
Elastic

Good to Go

Bing



Baidu (PRC)



Duck Duck Go



Majestic 12



Mojeek (UK)



FAROO



Search Tools

Elastic
Open Search Server
Google Custom Search