.racing - racing

.radio - radio stations

.realestate - real estate

.realtor - realtors

.realty - realty and housing

.recipes - Recipe sites, food & beverage grocery brands, health & fitness organizations,
                cooking enthusiasts, personal/professional chefs

.red - those who like the color red.  Also Spanish variant of .net.  Also likely to be
          attractive for domain hacks for words that end with '-red'.

.rehab - Physical and occupational therapists and professionals, drug, alcohol and gambling
              addiction counselors, rehabilitation facilities and recovery centers, online health
              directories, physical or emotional health associations

.reit - real estate investment trusts

.rent - Real estate professionals and small businesses

.rentals - Real estate brokers/agents, city guides, college housing centers, & community centers,
                vehicle, equipment, or entertainment/event rentals, property managers, condo/apartment
                developers

.repair - General or specialty repair shops, construction contractors/subcontractors, DIYers,
              appliance wholesalers & service, auto/boat businesses

.report - News & current events sites, financial reporting sites, financial or business analysts,
              consumer product reviews, police, school, or other community report listings

.republican - Political candidates, lobbyists, political parties, fundraising organizations

.rest - Restaurants and related industry

.restaurant - Casual eateries, gourmet restaurants, suppliers, chains, review sites, reservation
                      sites & services

.review - public reviews

.reviews - News media, food publications, travel publications, literary publications, any product &
                 service with online reviews

.rich - businesses catering to the wealthy

.rip - Loved ones seeking to memorialize the deceased, funeral homes and cemeteries, businesses
        that support the funeral industry, obituary websites

.rocks - Pop culture sites, niche and fan sites, musicians, gemstone & jewelry companies

.rodeo - Rodeo interest

.room - lodging or room design

.rugby - rugby

.run - Runners, running shoe retailers, specialty running gear shops, running event organizers