What effect do neutral buffs have in League of Legends?

Summoners Rift buffs:

Information applies to Pre-season 5 and can be subject to change

Crest of Cinders (Red buff)

Granted by killing the Red Brambleback in either the Northern or Southern jungle.

• Basic attacks slow the target's movement speed by (8-15)% for melee attacks and (5-10)% for ranged attacks for 3 seconds.
• Basic attacks also deal 5-56 true damage over 3 seconds.
• Grants health regeneration bonus of 1% maximum health every 5 seconds

Crest of Insight (Blue buff)

Granted by killing the Blue Sentinel in either the Eastern or Western jungle.

• Regenerates 25 mana per 5 seconds
• Regenerates .5% maximum mana (or energy) per second
• 10% cool-down reduction.
• Increases Max Energy (Cannot find source saying exact amount)

Both red and blue buffs last for 2 minutes without Runic Affinity and 2:24 minutes with it.

If slain, buffs held by the newly dead transfer to the killer.

Hand of Baron

• Grants up to 40 AD and AP scaling with game time
• Grants Empowered Recall reducing its channel time to 4 seconds. Successfully recalling will restore 50% of your maximum health and mana and grant 50% bonus movement speed for 8 seconds.
• Buffs all nearby minions and super minions (exact information can be found in the link).

Lasts for 3 minutes with or without Runic Affinity.

If slain, the buff is lost but not transferred unlike the blue and red buffs.

Dragon Slayer

This is a permanent team-wide buff that stacks with the number of your team's dragon kills.

1. Dragon's Might: +6% attack damage and ability power
2. Dragon's Wrath: +15% damage to towers and buildings
3. Dragon's Flight: +5% movement speed
4. Dragon's Dominance: +15% damage to minions and monsters
5. Aspect of the Dragon: Doubles all previous bonuses and your attacks burn for 150 true damage over 5 seconds, and also reveals the target for the duration. This stack only lasts 180 seconds.

Twisted Treeline buffs:

Crest of Crushing Wrath

Granted by killing Vilemaw, the boss monster located at the top of the map.

• Bonus health regeneration
• Bonus mana regeneration
• Increased attack speed
• 20% Cool-down reduction

(No source can be found with exact details, but this unspecific info was found on the wiki)

Lasts for 2:00 minutes or 2:24 with Runic Affinity.

If slain, buff is lost and not transferred (same as Hand of Baron on Summoner's Rift).

Altar buffs

• +3 gold on unit kill

• +3 gold on unit kill
• Adds +10% attack damage and ability power

Capturing an altar will give +80 gold to all players on the capturing team and vision of the altar

Buff is permanent as long as you own the altar.

Altars first open at the 3 minute mark and are locked for 90 seconds after being captured. Once unlocked the other team can capture and lock it for themselves, but the same altar cannot be captured by the team that already owns it.

Crystal Scar (Dominion) Buffs:

Shrines

• When walking over shrines, the player gains a 30% movement buff.

These areas are neutral, so both teams can utilize them.

lasts 10 seconds or 12 with runic affinity

Health Relics

• "It seems to give you 15 + 1.25 x level % of your champion's max health (Pending Testing.)"
• Add 2 points to your personal score

These areas are neutral, so both teams can utilize them.

Greater Relic / Storm Shield

Increased champion model size. - A shield of 212.5 (+12.5 x level). - Passively detonate a lightning blast inflicting 90 (+10 x level) magic damage on champion auto attacks and damaging spells.

Mark of the Conqueror

This buff is granted to the first team to complete a "quest" on dominion.

• +10% to all damage types

50 seconds or 1 minute with Runic Affinity

Proving Grounds (ARAM) Buffs:

(Same as Dominion Health Relic)

Health Relics

• On both maps, it seems to give you 15 + 1.25 x level % of your champion's max health (Pending Testing.)

These areas are neutral, so both teams can utilize them.

FORMATTING TAKEN FROM @theorise