So someone said: "Yeah, well if you're so bright, try to find four words in 'president'." Being a representative of the OCD community, I gave him this short list:

de di ed en er es et id in is it ne pe pi re si ti dee dei den des die din dip dis dit eds end ens ere ern ers ids ins ire its nee net nip nit ped pee pen per pes pet pie pin pis pit psi pst red ree rei rep res ret rid rin rip see sei sen ser set sin sip sir sit sri ted tee ten tie tin tip tis deep deer dees deet dene deni dens dent dere dies diet dine dins dint dips dipt dire dirt dite dits dree drip edit eide ends erne erns erst esne ides ired ires iter need neep nerd nest nets nide nips nite nits peds peed peen peer pees pein pend pens pent pere peri pert pest pets pied pier pies pine pins pint pirn pits pree rede reds reed rees rein reis rend rent reps rest rete rets ride rids rind rins ripe rips rise rite seed seen seep seer send sene sent sept sere side sine sipe sire site sned snip snit sped spin spit step stir teds teed tees tend tens tern tide tied tier ties tine tins tips tire tree tres trip deeps deers deets deist denes dense dents deter diene diets diner dines dints dirts dites drees drest dries drips dript edits eider ender enter ernes ester inept inert inset inter needs neeps neist nerds nerts nides niter nites nitre pedes peens peers peins peise pends penes penis peres peris perse peter piers pined pines pints pirns piste preed preen prees prese prest pride pried pries print prise redes redip reeds reest reins rends rente rents repin reset resid resin resit retie rides rinds rinse riped ripen ripes risen rites seder seine sente senti sered serin siped sired siree siren sited sneer snide snipe speed speer speir spend spent spied spier spine spire spirt spite spree sprit steed steep steer stein stere stern stied stipe stirp strep strid strip teens teind tends tense tepid terne terns terse tides tiers tined tines tired tires treed treen trees trend tried tries trine tripe trips denier denies denser desert desire deters dienes dieter diners dipnet direst driest eiders enders endite enters entire espied esprit estrin inerts insert instep inters nereid nereis nested nester niters nitres peined peised perdie pester peters pinder preens preset prides priest prints prised pterin redips redipt reedit reined renest rented rentes repent repine repins resend resent reside resite rested retied reties retine rident rinsed ripens ripest seined seiner sender serein serine sinter snider sniped sniper spider spined spinet spired spited sprent sprint sprite stiped stride stripe teinds tender tensed tenser ternes tiered tinder treens trends trepid triene triens trined trines tripes deniers despite destine diester dieters dipnets endites entires entries erepsin nereids penster pestier pinders preedit present preside pretend printed pterins reedits repents repined repines resined resited respite retines ripened serpent speired spender spiered spirted stipend striped tenders tinders trienes inserted nerdiest preedits pretends priested resident respited sintered spendier sprinted trendies president

Let me know if you find something I missed.